I will be kicking dead horse, but I randomly came across this here and skimmed through...
I have no problems merging the tags if that's how you want to play this, but in my opinion these two mean different things.
Shoujo Ai was originally about little girls at the age where they are not really emotionally developed to process romance and their friendship outgrowing the limits of "friend" and them trying to face the new emotions so from the old stuff I recall reading, it was generally about late elementary school or middle school aged girls usually in girls schools.
And as people repeated multiple times - yuri is an umbrella term for any girl/girl romance.
In other words just like Isekai is generally subgenre of fantasy, shoujo-ai is under yuri.
Also have no idea whether it worked similar with shounen-ai and yaoi. The only shounen-ai I read was probably
this.
To be absolutely honest, I personally would prefer adding tags, not removing.
-Like some that would convey basic tone of the titles would be nice. I mean just looking at isekai, you have wide swings between something like
this and
this
-One could also make an argument for adding tags for character traits of main cast...
-Tags describing how fast pacing is could also be useful.
Some might think that it might spoil the story, but syosetu, a novel website, has all of these covered and it is super useful.
Quite frankly overwhelming majority of my searches here were just a waste of time. It is better to first find a title on site like mangaupdates and then look for it here.