How will this be handled in a dispute? receiving sending the payment for that content> 
In this case, request the payment before providing the service, it's as simple as that. Large companies can afford running a Lightning Network node 24/7 so they won't even need watchtowers in case someone attempts to cheat by broadcasting an old state of the channel.
even though there's anonymity/privacy concern to both parties and anyone who use their channel to route transaction.
The nodes which route the payment don't know who initiated the transaction and what the destination is (assuming that they are not the first and the last node). Sharing the transaction history would be enough (more specifically - payment preimage is needed for each transaction since it's a proof of successful payment). Why are you so concerned about privacy when anyone can view the details of on-chain transactions? The Lightning Network helps to increase the level of privacy, but don't expect to be completely safe.
I'm not concerned about privacy, but few users surely have privacy concern. Even though they should privacy-focused cryptocurrency.
2. Scalability: I thought more scalability can be achieved by transacting off-chain, but if, when closing the channels, we must broadcast the same amount of on-chain transactions to spending funds from off-chain hash-locked outputs, won't it choke the blockchain all the same when we attempt to close the channels this way?
With the combination of other scaling solution such as Schnorr Signature (aka Signature Aggression), Channel Factories and eltoo, these will reduce total on-chain transaction count/size significantly.
Schnorr Signature basically makes transaction with multiple inputs only require 1 signature (which created from multiple input signature) which reduce TX size.
I barely understand about Channel Factories and eltoo, so i suggest you to check these site if you curious :
https://bitcoin.stackexchange.com/questions/67158/what-are-channel-factories-and-how-do-they-work/67187
https://blockstream.com/2018/04/30/eltoo-next-lightning.html