If only this were true. There are plenty of games where the frame rate is capped at 60hz because the physics engine is coupled to it. If you force a framerate increase via .ini tweaks or something, you get really weird physics. I think Skyrim had this problem. Also, there are examples of where changing the network tick rate [1] can affect the physics engines.
To me, that's bad software design. 40 years ago, developers used to sync their logic to the refresh cycles of the target machine's display. That's amazing, but also something that should not happen in 2018 (or 2010 or 1998).
For the younglings: it was a physical button to underclock the CPU on old PCs.
Can't a virtual world be built with the same principles?
The only place it might cause issues is if you need it to be deterministic, e.g. for multiplayer.
Obviously for most models it is simple to adapt to variable simulation periods without instability, either by microstepping (which commonly occurs anyway because the natural simulation freq is much faster than 60Hz), or because the process is just solving a stable DE or doing basic physics over a different period.
For debugging it is often much easier to run physics at a fixed rate. You do get different results at different rates due to numerical precision issues and error accumulation.