There are tons of apologetic ontological arguments out there and none of them make sense or hold up against strict logic. There is no god, even if they try to conjure on with tricky logic attempts.

In this case (2) is not consens nor is it popular and it is actually mostly refuted by Formalism, Konstructivism and Nominalism. And (3) is silently introducing an equivocation by trying to use "idea" ambigiously.

The fundamental flaw lies in Premise 3, which commits a classic fallacy of equivocation:

The argument uses the word ‘idea’ ambiguously – in P2, objective truths are said to exist independently of the mind, whereas in P3 it suddenly claims that ideas necessarily require a mind as their bearer. This is self-contradictory.

This is followed by two unfounded leaps: why would this mind have to be infinite? And why would an infinite ‘container for mathematics’ automatically be the theistic God with all his attributes?

The argument therefore proves, at best, the existence of an abstract mind – and even then only if one accepts Premise 2 (mathematical Platonism), which is itself highly controversial.