That works as long as on chain fees in bitcoin are reasonable, which they won't be forever. If we get a swap from LN or LQ btc to monero and back we might be talking... but I do have serious doubts to to financial regulations that a lot of companies will accept monero unfortunately... that was always the problem I had with designated priv coins in general. IMO we'd be better of to "trojan horse" them by first getting them to accept btc and afterwards adding privacy features they can't stop...
Discussion
You don't swap every time you want to spend
You swap a chunk into Monero that will last you X amount of time i.e. several weeks/months, and spend that Monero directly. Savings vs checkings model. If you're mainly a hodler I guess this doesn't help you though.
What is stopping you from using Bisq, Robosats, or Agoradesk to buy Bitcoin p2p and no-KYC?
You can also just buy Monero first (even from a CEX like Kraken if you must) and then swap into Bitcoin on a DEX or instant swapper. Link to your identity is actually broken this way if you do the random timing, amount split, IP mask thing we talked about earlier.
If regulators don't like Moneros strong effective privacy - they aren't going to allow strong effective privacy layers like Ecash
Feels like Tradfi is reverse trojan horsing BTC lately tbh
That still won't work with the 2Mb blocks we have rn... for now it does and it's a viable option.
The question isn't what's stopping me, the question is: what's stopping most people... and that's laziness. Hence the need for implemented privacy improvements to btc.