Stefan, I started running tubeless in 2017, 3 bikes originally but only 1 is still tubeless now. At first I loved it, but I'm becoming increasingly aware of the long term cost. Perhaps in a couple of years I'll gate tannus just as much?
Sliced sidewall on the norco in 2018 - I had a tube with me but couldn't be bothered fitting it trailside amongst the mess- only a 2 km walk, but that BRAND NEW tyre was thrown out instead of trying to clean / patch it a few thousand km from home.
The front recon that came standard on my full e was tossed out before its time. I had intended to use it on the rear but decided cleaning all the sealant wasn't worth the hassle ( to be fair , I never really liked the recon)
I've had 2 dhf's that had rub marks to the sidewall and developed slow leaks as a result - 2 nearly new tyres thrown out.
Multiple sets of rim tape - one nick with tyre levers and you pretty much have to replace it ( Eventually solved by moving to gorilla tape which is far more forgiving)
I've lost count of all the clogged valves that have been thrown out, or poorly sealing ones when a bit of sealant cures on the base .
Plus every tyre change means discarding the sealant that's inside the old tyre - we ride rocky terrain so wear through about 3 fronts on each bike each year , that's a few bottles of stans dumped down rabbit holes beside the shed....there's probably a very happy rabbit sleeping on a latex bed under there....
Don't get me wrong, I absolutely loved tubeless in the first year - no impact punctures , lighter wheels, it seemed too good to be true. I think those of us who keep bikes long term are learning tubeless comes at a price.