I discovered today that my most played game on Steam is Astronner with about 500 hours, and my second most played is Surviving Mars with about 500 hours.
In a year I had over 200 DAYS played on World of Warcraft back in 2005-2006. That's over 13 hours a day, then I quit abruptly and later tried a couple of expansions casually.
Second is probably Counter-Strike 1.#. No idea actual playing time but would estimate around 1000 hours.
The above two I don't regret spending my time in. Made a lot of friends and it all felt rewarding.
Then there are games like Civilization VI (~200 hours), Rimworld (~300 hours), Tropico (~200 hours) and even Path of Exile (~500 hours). These games are not really rewarding, other than little dopamine hits that gets you continuing playing forever.
Another WoW addict checking in. I was somewhere north of 12,000 hours from release to the end of Wrath with another stint during Classic.
I've since quit with no intention of ever returning. Despite how much I loved the game it doesn't love me back, and it's better if I don't play at all.