It matters, because it’s not about messages, it’s about the interface and all the logic which was built over a long period of time. Having an OS-native gui is better because it’s faster, it’s “already there” and not just loads, and it’s all done in the desktop app already.
As a good comparison - what would you choose for any service on your smartphone - an app or a really nice mobile website?
Why does it matter if it’s a web version, if all mail messages today are HTML anyway?
It’s actually the only program on the desktop that have valid reasons to be web-based.
It matters, because it’s not about messages, it’s about the interface and all the logic which was built over a long period of time. Having an OS-native gui is better because it’s faster, it’s “already there” and not just loads, and it’s all done in the desktop app already.
As a good comparison - what would you choose for any service on your smartphone - an app or a really nice mobile website?