>>49947354There are many more moves that are not like that than are, so unless you built your team specifically for triples, you probably won't have that chance super often, and a lot of the moves that would hit multiple targets in triples also hit your own mons, which limits what team combinations you can reasonably have out if you don't wanna constantly be shooting yourself in the foot. Besides, you can't just come out guns ablazing in competitive; you're probably gonna need to spend some turns setting up first, and even if you did, that doesn't solve any of the issues I listed with how many battle messages you'd have to click through every turn if triples were standard.
I'm not saying it's impossible to make triples standard with Pokemon, but I just think it'd get really tedious really fast with the current system.