If you're gonna say they don't, then the gen 4 evolutions of the old Pokemon don't count either. Now calculate how many new ones were there. I don't feel like it.
Do the same with gen 2 and 3 too, if you're going to do it, please. I'm pretty curious about the numbers of actual new Pokemon in those.
Sylveon also doesn't count as a completely new Pokemon. It came from Eevee.
You say it's not the same thing? Mega Evolutions. See that word? Sure, it's temporary, but it still counts. So, if you don't want to count Megas, your precious old Pokemon evolutions don't count either.
Now be quiet and do some calculating. I guarantee you than only gen 5 will show more than 100 actual new Pokemon. Well, actually, gen 3 might too.
While every detail of Mega Evolutions isn't known yet, from the current information they seem more like temporary Form Changes than actual evolutions. The pokemon changes, but not into a different creature.
As such, I don't count Megas in the number of new pokemon(not that it matters, anyway)
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