Depends on where you are - a SIM swap attack is surprisingly easy to do in many places.

But more generally, a sophisticated actor doesn't have to be targeting you specifically. Many people assume that "nobody would put in so much effort to steal from me", but they don't have to be. A sophisticated attacker with the capability to intercept SMS would likely be casting a very wide net. Once people start noticing, they'll be locked out very soon, so they'll be aiming to "hack" as many people as possible.

You might just happen to be one of the N random people that happened to log into their bank on the day of the hack and the spreadsheet happened to be sorted by last login time. Hackers don't discriminate, so as long as you fit "SELECT from account WHERE balance > 0", you'll be on the target list.