Yes it is a different kind of worth, but it is not worth less because of it.

This common argument to not take market cap valuations seriously doesn't hold.

True, Meta as an entire entity is not liquid. A forced sale in entirety would produce a massive reduction in compensation. But that is a highly unlikely and contingent reduction.

It is also true that if you have Meta's equivalent in cash, the value of the cash is likely to drop, while the value of Meta likely to grow, over any appreciable time. In that sense, $X cash is worth much "less" than the $X market cap.

These seeming contradictions are the result of different practical tradeoffs in structures of wealth. Not because market caps reflect misleading or overstated accounting.