Since my pc is like a 2004 pc that takes like 5 seconds to load every map, and in speedrunning, it would add alot of time. Like, if there's over 10 loading screens, it would be over 50 seconds of loading screens. (Sorry not sure if correct place to post this)

Depends on the game. Some games have 'Time without Loading' whiles others don't. If the game you're running does, then you can exclude them from your total time.

I do not suggest splicing your video to exclude load times or it could come under scrutiny.

5 seconds per load? You know how many games would benefit from 5 second loads? That's not bad. Sonic 06's time would be down by like a year if it had 5 second loads.

But back to your question. Even if a community timed without loads it's not a good idea to cut them out because that could turn to suspicion. No mater how many times you tell someone, you really don't have any proof that your run isn't spliced or anything UNLESS you have those loads.