I have several mails for different projects. Also private + university mail. Then I have my Google mail that I exclusively use for everything related to android/app store.
Checking all those mail accounts at once, managing folders/filters and signatures is all way easier with a desktop mail client.
Some years ago I was like you. I only needed to read mail and I have to admit that a desktop client is not really necessary in that case.
I tried. But Google Play store won't install it on my waydroid because the device is not verified and I don't think it is possible. Correct me if I'm wrong! :)