They absolutely are. NSA is obsessed with post-quantum projects atm

tbh they could just be pushing for people to adopt newer, less-tested, weaker algorithms. switch from something battle-hardened to the QuantResist2000 algorithm which they've figured out how to break with lattice reduction and a couple of GPUs like those minecraft guys did.

But is this because they are already needed or because they want to preserve encryption for past and present data post-quantum?

The latter