I use Firefox (and chromium and even chrome at work) and lemmy, but nothing comes close to Google search, maps and YouTube content. I tried ddg and openstreet maps, not even close. Partially because of crowd sourced, privacy invading features like location tracking for traffic info. I even pay for YouTube premium, easily the cheapest entertainment around. The ads in the free version is crap because how disruptive they are, and I prefer to pay the creators than use an ad blocker (although new pipe is on my phone and yt-dlg on my computer for videos I really like and want to preserve).
For email Google has features that other clients just don’t, even tho I ran my own server, DNS domain with dkim, etc, I still prefer Gmail for 90% of my emails. Only friends and family get my non-gmail account. Spam filter, calendar integration, mobile Client, threads, consistency, customization…
Same for office. While I do have Libre office installed (and Next Cloud on my server) I mostly use Google Docs. I never know who I will need to share a document with, or open on mobile or somewhere else, Google docs just works.
I also loved Google Reader and used Google domains, but I don’t want to talk about that :D