For when you have multiple accounts, yes.

I switched from containers to total cookie protection just for quality of life. It takes a lot less micromanagement of settings and still provides strong protection. I've not looked back since, and yes, I think it's more than sufficient for most people.

Nowadays cookies are becoming obsolete in the fingerprint process (of the users) then the major utility of containers will become obsolete too, in my opinion.

One thing that is really handy for development is that you can set up any container to use a proxy server. I use that a lot to reduce the sheer amount of crap that would get sent to the proxy if it were enabled at the system level or in the regular browser network settings. It really keeps the noise down.

Anything that is Facebook/Meta is in its own container for me. That way they can "track" as much as they want, they won't see new or even accurate Info.

They would be much more useful if we had per container, fine grain cookie exceptions, read this https://connect.mozilla.org/t5/discussions/cookies-improvement-meta-discussion/m-p/34997

I've had mine set up since launch and it works great. got certain types of sites/browsing dedicated to certain containers, along with cookie autodelete (it respects containers so can have settings per container) to delete cookies unless i whitelist a site.

I rarely use the containers. Instead I prefer to seperate activities with different versions of firefox. I use Firefox ESR for normal browsing, Firefox for VPN browsing and Firefox Dev/Chromium for school. I also use a different color scheme on each firefox so I do not confuse them.

I use it for YouTube. I have a throwaway account that I only use for my subscriptions. Dont use any other Google things, so I am signed out outside of that container.