Firefox profile management is clunky. Chrome multiple profiles are fast to switch between and the user interface is clear. You know which profile a window belongs too, you can see the name and the icon. Since I only use it to be logged in anyway, it's not a huge security concern. Consider if you have like 20 profiles and you want to switch between them.
Firefox account containers are very clean and easy for this. The tabs get colour coded based on which account is logged in and you can configure certain sites to always open in certain containers.
I want to trust Firefox containers, but it's always been ambiguous to me. I like the very clean separation of profiles. The ability to change theme/colors of profiles.
If I have multiple Gmail accounts for instance, I don't think Firefox containers help me.
Yeah, that's what they're for. Having multiple accounts separated and not interfering with each other. So you can have eg. three different tabs of Gmail open or office or whatever in the same window with different accounts logged in. Each tab with a different colour. Great for separating work stuff from personal stuff or isolating bank logins etc.
Sounds like the same thing as you're describing in chrome (though I haven't tried the chrome implementation)