I just can't see tubeless ever becoming reliable enough to be able to trust it on high pressure road tyres, without carrying tubes and repair kit as back-up, which rather defeats the object of going tubeless. The problem seems to be that the sealant won't coagulate because there is enough air pressure behind it to force it through the hole whilst still liquid.
MTB users tend to report better results because their tyres only run at half the pressure and have two or three times more air volume, so the leak will seal faster and a small loss of pressure won't risk unseating the tyre off the rim.
The industry will push tubeless for the same reason they push 11 speed and disc brakes - because they are constantly fighting a battle to make cyclists update and replace serviceable equipment that doesn't actually need to be updated. The industry don't like cyclists like me who will buy something just the once then keep running it for years and years without replacing it with something different and putting more money in their pockets.
Bicycles are a mature technology and had already reached a level of development which gave mechanical durability and reliability decades ago, at which point many riders will just stick with what they have. Rigid steel frames don't wear out, so once the market is saturated with rim-braked rigid Road, Hybrid, and MTB's, sales are pretty much limited to maintenance parts. All the recent industry trends are aimed at displacing the low-revenue type of bikes with ones that offer a more frequent replacement/upgrade cycle, and more expensive maintenance parts pricing. Tubeless is part of this strategy.