It's not overnight, even btc it's not widely viewed as SOV, still XMR is loosing against BTC. There will be many BTC L2s some with great privacy, all interoptable through LN. Ark protocol will have good privacy, there will be many options, each person will choose his protocol and pay/receive through LN.
Discussion
When that option come, if they are better than monero why would i change?
Until then i use the best solution i know 😉
Ofc you will only change if they are better in your view, but over time if btc keeps being better SOV than XMR, then with more bitcoin acceptance everywhere, you will have less reasons to keep XMR if it's not widely accepted like BTC and with good privacy options on BTC. Until then yes, XMR is probably better for privacy.
And if a better tool borns in the future than both i will migrate to that tool, thats how world works.
All these privacy L2s so far are custodial, permissioned, or require intermediaries (ecash, liquid, lightning, etc)
You can have privacy AND sovereignty with Monero