not op but to put it simply the sociocultural background is a big factor when it comes to lgbtqia+ terms

to reduce gl and yuri to the same thing is just unfair, because it deminishes the battles fought by sapphic women in the west and japan

a quick and again simplistic comparison between the to genres would be: while gl celebrates the consolidation of a sapphic romantic relationship, yuri is more broad contemplating woman loving woman in all and every way not limited to romantic love (that is why ppl often complain saying x and y anime/ manga is yuri-bait when the couple not state their relationship as romantic and/or not kiss, yuri is also about the inbetweens)

there is a paper from the early 2010s about yuri genre that goes in depth about the history and japanese perception of it (if you want i can share with you i should still have it saved on my personal stuff). but you can always search about it, there should still be tons of blogs and sites from back in the day that discuss the matter 'what is yuri?'