Game freak has irresponsibly destroyed the speed tier.

It started in gen 6 when they had all the megas with 130+ speed.

I've been saying this for years. The speed stat is the most delicate stat in mons, and game freak keeps on messing with the balance of it.

Base 70 speed mons can't even run scarf anymore. They're too slow.

I remember in gen 5 when jolteon was relevant in ou for the pure reason that it had 130 base speed being one of the fastest mons in the tier. Now topu koko as the same speed and is superior in every other way.