Just make everything a link (a tag) unless you can't. Doesn't matter how it looks like. It can be some text with underline or it could look like a button. Even

Just make everything a link (a tag) unless you can't. Doesn't matter how it looks like. It can be some text with underline or it could look like a button. Even if the button only does some action on the page, it could still be represented with a url. Sometimes it doesn't make sense. Then that's the time to use something other than an a tag. If this were the default, most of this problem wouldn't exist.