log in problems on multiple sites since sonoma 14.1.1

Have there been some kind of security(?) updates with 14.1.1 or maybe the update before that? I'm having all kinds of trouble logging into various websites, often but not exclusively told they don't recognize my email address. I've used only Safari for years and am tired of being told to try a different browser. In the past few weeks, this has happened with retailers, a bank website, and at least once on a medical site, maybe more than once. I don't think *I've* changed any setting that would do something like this and have no idea what could be going on.

I can't provide screen shots because the ones I have show my email address, and I don't know how to block it. One example would be Kohl's, where I shop regularly. Starting 3+ weeks ago, I started getting "something went wrong. Please try again" after typing in only my email address. A couple of days ago, that switched to "you can't sign in right now. To protect our customer's (sic), we monitor for bot activities and it looks like you've hit one of our indicators." ??? That would have somewhat made sense if it was on one of the days Kohl's employees had me make multiple log-in attempts in fairly short order, but no. This comes up when it's a one-time thing.

A bank who we have a credit card with said it didn't recognize my information.

I tried to pay a medical bill and that site said it couldn't log me in.

Didn't take notes on every website where it's happened because I didn't realize it was going to become a regular thing.

While I have been able to log into FB mostly without problems, I'm periodically getting a msg that says something like "if you're have trouble with this site, reload with reduced protections." No idea if this is related to the above.

I'm on an iMac refurb purchased in 2022 that I believe was originally a 2019 computer, if that helps.