I have bar end shifters on my touring bike, but only because that was what I had when I built the bike.

When SHimano first introduced their STI dual-control levers, like in the early '90s, there were reliability problems. In the ensuing 30 years, STI levers have just about perfect reliability. As someone else said, it is possible to break them in a crash (like anything) but I have seen a lot of them with cosmetic damage from crashing but still function just fine.

Also, since they are pretty common on bikes now, replacement levers are generally easy to get hold of if you should need it.

Bar end and DT shifters can likely by kludged back together in an emergency but for dual control levers, this would be much more difficult or impossible. For the ultra-eXXXtreme self supported adventure touring in developing countries, this could make a difference, but otherwise STI levers are the cat's pyjamas.