Can post-quantum algorithms be run on commercial devices? Noob alert! Can we run quantum safe algorithms on commercial devices (like phones, laptops, etc)? I've seen some messaging apps and vpn providers marketing themselves as quantum-proof. How likely is that all these claims are bogus for marketing (imo, very)?
Post-quantum cryptography addresses the problem of developing public-schemes whose underlying assumptions are (believed to be) quantum resilient, i.e., the assumptions hold even in the presence of quantum computers.

There are many proposals for the underlying assumption and this leads to several branches like lattice-based cryptography, multivariate cryptography, code-based cryptography, hash-based cryptography or isogeny-based cryptography, among others.
The cool thing about these assumptions and techniques is that they can be implemented in classical computers.
In fact, many of these are already implemented and there is a competition driven by NIST to standardize some of these.

So, yes, these primitives are usable nowadays. Maybe these companies use a scheme of this nature, that may be the case.