Not only that, but most philosophers who specialize in the philosophy of mathematics are Platonists: https://philpapers.org/surveys/results.pl?affil=Target+facul.... IME, this is also true of working mathematicians, but much less true of physicists.
This is not accurate. Platonism, in a contemporary context, is the view that abstract objects exist. And so in particular to be platonist about mathematics is to believe in the existence of mathematical entities.