I used to prefer being DPS. And then I played the first game that made healers and tanks fun for me. Shaiya. Wasn't the best game overall. Kinda bad, and a ripoff of some parts of WoW. But it was fun to heal in, and very fun to tank in. You really could change the entire gameplay based on how you tanked, and how you healed.
Then I moved over to battle/war of the immortals. Again, flawed games, but tanking and healing were fun. Healing more than tanking in those two, but still more fun than DPS.
When I switched over to Neverwinter as my main gaming focus, the way they had the classes be able to handle tanking and/or healing was the most fun I'd ever had playing in PUGs. I could pop onto my haste cleric, keep everyone alive while also boosting them and put out play damage solo. Paladin? Same idea, only the team wouldn't get hit much if at all. The fighter class was essentially pure tank, and good at it, but not as much fun as paladin for me.
I had more fun playing supports, heals and tanks than I ever did on DPS. It didn't hurt that, on the games I played, I was great at tanking and healing. Enough so that my guilds/alliances would plan events around my schedule, even when the people were on the other side of the planet. Even on Shaiya, which was totally pay to win, I could out heal and out tank players that dumped tons of cash into it.
I miss it sometimes, but I'd have to rebuild my gaming PC to be able to play neverwinter now, because no way am I starting completely over on the ps5 with a controller that makes it much harder to play those classes. And none of the console based MMOs really entice me currently.
Honestly, this just highlights how badly thought out the gameplay is for non-dps classes in a lot of games. So often, both the healer and tank are left as second-class citizens, as all the emphasis is put on killing enemies. For example, in Overwatch, while tanks and healers were effective, there was little depth and little reward in the role compared to DPS characters. Orisa was a dps who couldn't leave the objective and had to hit 'e' on the ground every few seconds. Mercy just followed someone around, with little agency of their own. Compare that with, for example, Junkrat, where you were encouraged to be flying around the map, bouncing grenades off walls to make yourself near impossible to hit while still killing dozens of enemies. Theres both more depth, and more frequent, significant gratification. This is a big part of why I like Dota - supports (tanks aren't really a thing in the same sense) have a whole separate game they tend to be playing to manipulate the map in their favour, and can still impact fights with a plethora of significant abilities that are flashy and impactful in their own right.