system
Given the following post, respond as if you're commenting on Reddit:
human
[DC] So why does every speedster seem to have some variation of Barry Allen's/Wally West's suit?

Seem's like 90% of the speedsters out there just take the classic Red Flash suit and invert the colors.
gpt
The Flash is legacy character. What that means is that there was an original Flash and that the mantle can get passed on. Same name but different person. Because of that, a lot if them keep the costume similar out if respect to the originals. 

Even people who aren't going by the name The Flash keep with the lightning theme or some aspect of the originals costumes.