They took the most upvoted ideas from the community forum and started implementing them. Maybe to win some users over, but I think it might be too late for this to have any impact on market share.
I'm also kinda disappointed they just copied the UI from Chrome instead of releasing a refreshed version of the previous implementation. Old Firefox tab groups were like Safari tab groups (or "workspaces" in Edge, Vivaldi, Zen and maybe others), and I think they are way better for organisation. Yeah, STG extension still exists, but having it built-in would be nice.
The chrome implementation is way better than of Safari. I don't use the Safari tab groups because they lack features like pinned groups which i need to find it useful.
The Chrome tab groups are less useful as they don't really present a single workspace with only the tabs from that group, they are just literally a grouping of tabs all within a single workspace.
I use tab groups to switch tabs based on projects and I want full separation of those tab groups. The Chrome and new Firefox groups don't do that.
Now that Safari has them, I guess there’s pressure to have feature parity?