You’re all over the place. Please explain why you think using underpowered hardware is the only legitimate way to write software that works on that hardware.
Testing only in a VM on a beefy dev box leads to terribly performing software on customer machines. There's a multitude of performance problems that only come up when a system starts paging to disk, a machine has a HDD, or a CPU gets maxed out. These issues will be completely occulted on a dev machine with tons of RAM, 16 cores, and an NVMe disk.
Far too many developers have the beefy dev box with no requirements to test on more prosaic configurations. Even limiting a VM's CPU and memory isn't a good environment for performance testing because it's still faster than actual low end hardware.
In particular I often fight the slowest machine leaving the office. That should stay for a long time, set aside for testing.