I seem to have less and less control over where and how I am allowed to sign in (even thought I'm using a U2F key), and as a result I'm definitely getting pushed closer to the threshold to move away from gmail out of lockout anxiety.
[edit]
To all those comments that assume I'm: running an outdated browser, have a broken profile, am running untrustworthy plugins, am doing UA spoofing or have been pwned etc etc...
First you are missing the point: I dislike being held to increasingly arbitrary and opaque metrics of what Google defines as "safe"... because that is anxiety inducing, what will it be next week? even if I can log in now, will I be able to log in then?
Second: No, this is Google's fault, not mine. I have not been pwned, this occurs through multiple OS installs. I always keep my browser(s) up to date (i'm a web dev), I know the implications of runing lots of plugins (I do not). However i DO employ restrictions as do many HN readers that Google will find undesirable, uBlock Origin, Firefox enhanced tracking protection, block third part cookies, DNS level ad and tracker blocking etc... It's likely Google doesn't like one of these, but back to point no. 1: it's an opaque metric, I do not like this... hell it may even be because i'm running Linux - so maybe I should do UA spoofing after all to pretend to be a "normal" Windows or Mac user.