Although sub-penny microtransactions are not economically feasible with credit cards
nor current crypto-currencies because the fees are too high, these systems could in theory lower costs enough to lower fees to a percentage of the value of the transaction (assuming transaction values are not hidden with homomorphic encryption, because in which case the oligarchy centralization inherent in these system
has an incentive to raise to fees to what the market will bear cutting out lower valued transactions).
Millions-of-transactions-per-second scalable instant transactions are not feasible in either centralized database systems such as Apple Pay nor in any decentralized crypto-currency yet devised.
Centralized database systems have (afaics insolubly) greater latency due to the requirement for a roundtrip network query on the centralized database because unlike for a crypto-currency full node, the transaction can't be verified autonomously by a merchant. Additionally centralized database systems don't scale network effects as well (meaning they can't be ubiquitous[1]), because being a single-point-of-control power vacuum that demands vested interest conflicts.
The state-of-the-art crypto-currencies are (not only are centralized due to economies-of-scale, yet also are) are incapable of scaling up instant transactions and remaining decentralized. I have an idea of how to solve this, but my white paper is not yet published. Some dubious designs (e.g. VanillaCoin's Zerotime) have been presented which rely on propagation and node voting, yet don't scale and are susceptible to Sybil attacks. Other designs (e.g. Dash's InstantX/Evolution masternodes and Bitshares' Delegated Proof-of-Stake) rely on the centralization of
proof-of-stake which destroys the Nash equilibrium security in a power vacuum winner-take-all political economics. The hyped Lightning Networks (LN) proposes to
centralize off-chain instant transactions in order to scale, but it places a huge garbage collection headroom load on the block size which exacerbates the insoluble Bitcoin scalepocalpyse it portends to solve! Also LN doesn't enable anyone to pay anyone spontaneously as they first need to enroll in time locked channel deposits on the block chain.
Microtransactions
have been criticized for the cognitive load they place on the consumer and that consumers prefer to reason about all-you-can-eat subscriptions than the nickel and diming of microtransactions.
However there are use cases for microtransactions which can't be fulfilled with subscriptions nor existing alternatives such as advertising revenue. For example, advertising monetization
just doesn't work well for indie content such as music and
probably also not for games. Pharrells Happy streamed 43 Million Times, yet earned less than $3,000 for the musician. The
8 Core Drivers in gamification includes
Epic Meaning & Calling,
Empowerment of Creativity & Feedback,
Ownership & Possession,
Social Influence & Relatedness,
Scarcity & Impatience, and
Unpredictability & Curiosity engender use cases such as for example rewarding indie musicians and developers a fraction of a penny for each stream play or a small payment for game paraphernalia. Smaller payment choices might monetize more of the
users who value their time less. Subscriptions would be required with each musician or game, which would disincentivize the spur-of-moment impatience driver because of the cognitive load on choosing which of the unbounded quantity of choices to subscribe to. Or subscriptions would need to be centralized (acting a middle man between payers and payees) which then incurs the vested interest power vacuum scaling problem, as well as needing to register with FinCEN as a money services business which further limits scaling due to onerous KYC requirements.
Centralization sucks because it
stomps on the network effects of the free market.
...
Btw, proof-of-stake will never scale out user adoption, because it is a vested interest paradigm, and thus will be destroyed by its stake holders. No stake holder (in any context or business model) allows a competitor to profit. Only permissionless, decentralized systems scale.
[1] A prime example of this is how the oligarchy of credit card companies hasn't innovated internet payments and has strangled use cases, some of which are enumerated in this post.
Replacing Cryptonote rings with RingCT value hiding is probably incompatible with microtransactions-at-scale in all current block chain designs because (including Monero) they don't remain decentralized at-scale, but not that was Monero's focus any way:
Although sub-penny microtransactions are not economically feasible with credit cards
nor current crypto-currencies because the fees are too high, these systems could in theory lower costs enough to lower fees to a percentage of the value of the transaction (
assuming transaction values are not hidden with homomorphic encryption, because in which case the oligarchy centralization inherent in these system
has an incentive to raise to fees to what the market will bear cutting out lower valued transactions).
...
Dunno if i grasp your intention at full spec, but microtransactions we´re never intented to be populating the mainchain --->
https://getmonero.org/design-goals/Side-chains and daughter-chains (even if merged-mined) have very negative implications on security for the main chain.
Nevertheless, the core issues of scaling the design still need to be solved for the daughter chain, which no one has solved yet. Or you go off-chain, which has another set of insoluble issues.
So we might as well just say Monero isn't going to do anyone-to-anyone-spontaneously microtransactions-at-scale. Until I see a detailed technical refutation, I will assert that from my knowledge base on this area of expertise.
Edit: RingCT I presume is optional. So those who want to present the value of their transaction, so that an oligarchy could apply a lower fee (without destroying their ability to charge the highest fee the market will bear), would still work for users that chose not to hide the value of their microtransactions.