Excitable Boy
is a metaphor
Sylveon has Shadow Ball, which complements Fairy STAB to hit everything except lolPyroar neutrally, something Florges can't boast.
...How?
1.3 * 90 == 117 > 95. The increase in power about about 20 bp makes up for the marginal disadvantage in SpA.
The HP is what makes Sylveon better. Tanks want HP, especially if they're passing Wishes; Sylveon takes physical hits slightly better than Florges and special hits slightly worse, on top of hitting harder and having more relevant moves.
252 Atk Genesect Iron Head vs. 252 HP / 252+ Def Florges: 228-270 (63.3 - 75%)
252 Atk Genesect Iron Head vs. 252 HP / 244+ Def Sylveon: 236-278 (59.8 - 70.5%)
252 SpA Genesect Flash Cannon vs. 252 HP / 4 SpD Florges: 170-204 (47.2 - 56.6%)
252 SpA Genesect Flash Cannon vs. 252 HP / 0 SpD Sylveon: 198-234 (50.2 - 59.3%)
Pixillate is alright, but your argument for hyper voice is invalid with Moonblast
...How?
1.3 * 90 == 117 > 95. The increase in power about about 20 bp makes up for the marginal disadvantage in SpA.
Not to mention HP is the only major buff that Sylveon has over Florges. I can see a good Stored Power set with calm mind on Sylveon, but other than that, Florges has pretty much the same set ups, but better.
The HP is what makes Sylveon better. Tanks want HP, especially if they're passing Wishes; Sylveon takes physical hits slightly better than Florges and special hits slightly worse, on top of hitting harder and having more relevant moves.
252 Atk Genesect Iron Head vs. 252 HP / 252+ Def Florges: 228-270 (63.3 - 75%)
252 Atk Genesect Iron Head vs. 252 HP / 244+ Def Sylveon: 236-278 (59.8 - 70.5%)
252 SpA Genesect Flash Cannon vs. 252 HP / 4 SpD Florges: 170-204 (47.2 - 56.6%)
252 SpA Genesect Flash Cannon vs. 252 HP / 0 SpD Sylveon: 198-234 (50.2 - 59.3%)