Regarding what the owners fund, it's their money. Those who don't want to work or shop there need not do so. Those for whom that is not enough are free to whine and demonstrate.
The 4th amendment is narrow:
"Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof"
There is no established federal religion; I'm almost certain there are no established state religions (maybe there is an obscure law on the books somewhere that amounts to one?) for Congress to try to disestablish. Other than that, Congress is restrained from prohibiting the free exercise of religion, but not from accommodating it. I'd expect to see more accommodation (public monuments, open expression, etc) rather than less, of all religions that care to assert a public presence.
It sure is easy to become oppressive while claiming to fight oppression.
Push too hard against peoples' freedoms to express their cultural quiffs - particularly among enclaves of themselves - and they will push back (as we have seen). On this point, I don't mean to argue that it is right or required to yield, only that it is practical. It was stupid to drive evangelicals into Trump's camp, but Democrats were - and still are - determined to leave no refuge for religion anywhere in public life.