Okay, thank you for all the help.
What rapid responses! I’m officially impressed. I didn’t even think my post went through, since I didn’t get a confirmation and there was apparently a delay in it showing up on the forum.
I was pretty apprehensive about disabling plugins and changing the theme, so I ran a backup first. Then I deactivated all the plugins, and the issue remained.
So I changed the theme to Twenty-Sixteen, and that didn’t help either.
I didn’t quite follow the remaining conversations. Is it possible, then, that it’s the hosting provider, which is somehow disabling the rss feed functionality to reduce server traffic?
I like the ability to configure css/html/php code to really cater the site (and to better learn those languages). Sacrificing RSS feed functionality is preferred if that’s all I’m losing by staying with byethost. I really considered WordPress.com, but I couldn’t figure out how to alter source code. Perhaps there is a plugin, which can API into WordPress.com? I didn’t find one.