When I first saw these at a bike show, I asked how you're supposed to fix a flat on the road. The man said, "You just put a tube in it." I said, "Oh, great! Now I get to fix it twice—once out on the road, and then again at home if I want it to be tubeless again." Now they use a sealant liquid which is supposed to reduce that need; but it only lasts something like six months. I go at least that long without having to fix a flat with my tubed tires anyway! You also need a special pump to blast the bead against the rim to establish the initial seal.
A couple of my friends have tried tubeless, and did not appreciate having their legs sprayed with sealant when they did get a puncture. Further, a tubeless tire with sealant has just as much rolling resistance as a non-tubeless with a thin latex tube in it. I've also seen video of a bead breaking away from the rim in a corner and the sealant sprayed out even without a puncture.
At the show, the value initially touted for tubeless is that you won't get pinch flats. Almost none of the flats I get are pinch flats. The last time I got a pinch flat was many years ago; but if you don't keep enough pressure in the tires to avoid pinch flats with tubes, you'll damage the rims when you bottom out, especially now I'm sure with the hookless rims made to reduce wind resistance. When I did get a pinch flat, it was because I hit some railroad tracks so hard it seemed like it would break the wheels. It did crack the rim; and a cracked rim won't hold air like a new tube will, and it will be a lot more expensive to fix. Leave the tubeless for cars!