Rebasing to squash commits or even split commits up before/during making a PR makes sense to me and I do it all the time just to clean up my mess. The order of development and the state of the repo over time isn't faked, this is just labelling and granularity.
What doesn't make sense to me is rebasing instead of merging. If master has a lot of changes and you want to pick those up, you can merge in which case history reflects reality - each commit has an actual state of the repo that you had on your machine.
Or you can rebase, in which case all of the commits on your branch now contain code that no-one ever had on their machine, not tested, never run, maybe it doesn't compile, maybe it's nonsense.
Both result in the same diff from master so are equivalent for submitting a patchset.
It's really hard for me to see the value of trashing your history like that. People like linear history but history actually is not linear sometimes.