The Hindu desire to discriminate against other religions is fed by a very specific kind of hypocrisy - choosing the parameters of what "religion" means. So Hijab becomes a religious practice but the Brahmin janeu doesn't. So Namaz becomes a religious practice but public celebration of Hindu festivals doesn't.
The Hindu wants to create categories to discriminate against "religion" but doesn't want to fall into those categories himself. And when things become difficult to define, he conveniently shifts his religion into the "culture" folder.
This way, he becomes automatically immune to everything one might object to about a "religion". The Hindu wants to decide what criteria to allow or not to allow when defining religion. Unfortunately for him, his own religion catches fire when he does so. The only way to protect it is through hypocrisy - by pretending to not understand when it is pointed out that "essential religious practices" is a ridiculous thing.
No religion is essential. But that can't be accepted, can it? So folders are created to define religiosity and then every faith except Hinduism is put in them.
Think about it. There is no real reason why Namaz in public is objectionable but a puja procession is not. There is no real reason why the Hijab is problematic but a Saree is not. These are manufactured differences designed to discriminate.
Want to keep religion out, do it uniformly across the board. Don't do this seemingly progressive nautanki where you only pretend to care about religion being shoved into public spaces but actually continue to support your own religion being pretty much ubiquitously visible no matter where one looks.