Profile switching takes more steps to use than container tabs: 0.

If you think different profiles is comprable to container tabs, you haven't really understood how to use container tabs, or possibly even what container tabs are for.

No, container tabs are fundamentally different than just supporting different profiles, in that how it extends that concept allows for a whole new mode of use. Container tabs allows for domains to be tagged to always (or sometimes, with a prompt) open in a specific container, so after you've correctly configured it, you don't ever have to switch profiles. If I click a link to Amazon, it opens in my Amazon/shopping container. If I open a link to Goodreads, it does the same. If I open a link to any of the banking sites I need to use for different car/house/card payments, that automatically goes in it's own container.

The big thing that's different with container tabs is that after you set it up (which is done little by little as you decide to open something in a specific tab and then mark it to always open there), it's not something you actively manage, it passively does what you want. That's why it's so different.

Having every site be it's own container (which is also a mode Firefox supports, to my knowledge) would be slightly more passive, but also likely cause problems with some sites that use multiple domains, so I think container tabs is a good compromise (for now) that allows good compartmentalization while also allowing escape hatches for sires that require it.