This really isn't true. One of the most famous speedrunning games is Super Metroid, and its two glitchless categories are the most actively competitive ones. Oc

This really isn't true. One of the most famous speedrunning games is Super Metroid, and its two glitchless categories are the most actively competitive ones. Ocarina of Time glitchless had a new world record a few months back. Glitched speedruns tend to get more coverage in gaming media (because "runner completely breaks game" is clickier than "runner plays game 0:01 faster than previous runner"), and they tend to show up a lot at marathons (because they're faster), but generally speaking if you don't like seeing glitches there is plenty of content out there for you.