They cannot if the person uses Bitcoin properly Even if the person isn’t careful all you have is assumptions And they ALWAYS can using banking system

I am in Bitcoin since 2010. On-boarded many many people over the years and still I don't know anybody who is capable of managing their privacy "properly" with Bitcoin. I started onboarding new people yo Monero, as 99% of the people will NEVER figure out how to do it properly. They are a risk for themselves and for others if using Bitcoin assuming pseudonymity is enough. There is no pseudonymity in trades as people know their counterparties. Add yo that that most people bought KYC Bitcoins it is even worse. You are actively endangering people if you are not revising your stance.

What's the best way to acquire monero

If you accept small risk using instant exchangers, go on trocador.app (best used with tor browser on safest security setting, their onion address is on the website) and swapping from whatever coin you have like Bitcoin. Like another user suggested, Retoswap and Eigenwallet are two trustless/trust minimized options at the expense of convenience (always a worthy trade-off but don't let perfect be the enemy of good)