I have a foot in both camps. On my MTB I switched from tubes to tubeless about 3 years ago - result: not a single tyre-related incident on the trail since then (compared to a worse case of 4 punctures in one ride). When I replaced the tyres last time I pulled several thorns out of each tyre - each one would have been a puncture to repair, plus the countless ones that didn't stick around. I got a new MTB this week which arrived with tyres already mounted - I quickly worked out this has come already set up for tubeless (loosen the valve collar and push into the wheel - if it is a tube it will push in and deflect back - if it is tubeless it will either not move or will move and immediately start hissing air and possibly sealant at you).
My road and gravel bikes are all tubed. The gravel bike because I simply haven't got around to going tubeless yet. The road bikes because I am yet to be convinced of the benefit, given that I don't suffer anything like the number of punctures on the road as I do on the trail. In fact bar one particular ride, over roads coated with rain-washed gravel, I have not had a puncture on the road. I run Schwalbe Durano Raceguard tyres.
One benefit I did notice on the MTB was a noticeable impact on the mass of each wheel, both in climbing and overall speed.