I think it is worth noting that chainanalysis is based on very weak heutistics.
The reality is there is nothing linking an address to another one. (taking to the extreme, even a transaction with one input and one output). And each steps those heuristics become weaker and weaker every step down the chain analysis.
indeed, there are layers upon layers of deniability baked in. there are other privacy pitfalls that could play a role, like
browser/cookie analysis and IP address/bloom filter analysis by adversarial nodes. even then, the notion of getting a jury to convict based on this kind of chain of evidence is a tossup at best. blockchain analysis companies are generally working off a huge number of assumptions and that will become obvious to any jurors studying their protocols.
By the way batch transactions (output aggregation) togheter with coinjoin (input + output aggregation) are the best practices to transact over the bitcoin protocol. The fact that these techniques aren't implemented in "basic" wallets is not relevant. Everyone should always transact this way for every of his transaction.
in theory (actually this is arguable since coinjoin transactions are always currently more expensive).
in practice, most coinjoins are very obvious on-chain,
and some exchange customers are paying the price for it. taproot, cross-input aggregation, and less obvious coinjoin mechanisms will mitigate this in the future, but for now all i can say is,
be careful of your proximity to exchanges and AML/KYC enforcing services when engaging in coinjoins.