This honestly depends on the game. Some games take a lot of skill with only a little luck involved, while others require an unholy amount of luck to speedrun. From what I heard, a lot of people prefer speedrunning games that don't require you to grind for 0.00001% of some random shit happening because it's not fun at all however there's a "special" types of people who spent literall years of their lives trying to get that random 0.00001% of some random shit happening just because they want to be first one in the world to achive that, which is quite pathetic tbh
This post has already explained that there are various types of games, some involving luck and others not. I'll take on the (((trans question))) instead since some people mentioned it in the thread.
Trans people want others to believe they are the best at games despite only being over represented in female only categories. They can dominate real women instead of competing with their fellow men, since they will always be crushed there.
Speedrunning games with minimal amount of luck, and mechanically intensive:
https://www.speedrun.com/ngnes | Every top 3 for all category are all normal men.
https://www.speedrun.com/sm64 | Every top 3 for all category are all normal men.
https://www.speedrun.com/supermetroid | Every top 3 for all category are all normal men.
https://www.speedrun.com/smo | Every top 3 for all category are all normal men.
I can go on
Hollow Knight:
A 112% clear for a 2+ hours run has all top 3 players being normal men.
An any% clear which is shorter, for around a 30+ minutes clear have 2 of the top 3 players having they/them as pronouns.
Even with games that are easily influenced by luck, will you still have trouble seeing them, example below.
Minecraft:
Any% glitch category set seed and random seed both top 3 have a total of 5 trans people out of 6 in it.
Any% glitchless category have all top 10 players in both random seeds and set seed being all normal young men.
Despite having minimal amount of luck and high to moderate amount of skills, some games will have a huge trans playerbase because of its pro trans reputation/fan base/content, examples:
Celeste (Trans dev/flag in the game)
Ultrakill (Same here)
A Hat In Time
Undertale
Meaning their over representation is because of the game itself, not speedrunning.
And to add to the topic:
For some games, speedrunning is just the same as racing for a 100m, during a race your time will be influenced by your mood, weather, diet, shoes, etc. And in the case of an official race, you can control as much external factor as you want, but you can always put things under a microscope enough that you can deduce some amount of luck somewhere.
And for other games, speedrunning IS similar to gambling, you're wishing for luck to be on your side, but it is healthier than gambling, I doubt anyone would argue about this. But it is not a speedrunning thing, it's about the games themselves.
And then you have the games that are about both. Or that will need some amount of luck to beat a certain time/reach a certain placement.