Note that Windows will boot just fine on a disk with multiple ESPs

Nice for Windows to support this theoretically but the UEFI standard does not require support for multiple ESPs on a disk, so you will easily find hardware that in fact will simply discover the first ESP then stop. Because actual implementations matter and a lot of them are bad.

Speaking of bad implementations. We got several manufacturers a few years ago where their UEFI implementation broke and bricked the whole device after editing the EFI entries via efibootmgr exactly as defined by standard. Oh, you wanted to install Linux? Your device is now done because no one ever tested them without anything but the Windows pre-installs.

Yet two other cases of totally coincidental "This should work but doesn't, must be a Linux issue" artificially created by Microsoft (who after all were one of the driving forces behind UEFI development, also the reason we are still stuck with FAT32 ESPs - the only file system ESPs are required to support by the standard with everything else optional).

Windows never touched the main EFI entry in my cases

In the end positive anecdotal experiences don't matter much. If a relevant fraction of users has issues that should not exist when installing Linux (and that obviously don't exist with Windows because here OEMs actually do proper testing here... or it's Windows/Microsoft itself causing the issues (pre-installed key, fast boot shenanigans, hardware that should be supported but randomly isn't etc.)) that's helping to prevent a lot of people from trying it in the first place. And that's by design.