It is possible to allocate every object in its own page. In practice this is useful as a debugging tool but far too expensive for day-to-day operation.

Maybe the real issue to solve is to reduce the page size to make this a feasible approach to mitigation. Hardware designers have made this choice, but, does it really need to be 4096 bytes?

With a much smaller size, say, 128 bytes, almost every new allocation could be put into a new page at a new address, with one or more guard pages behind it.

Yes, it would increase the size of the page tables, and the lookup time, but maybe it's worth it.