Classical Greek texts with macrons?

This, of course, has a great deal to do with the way English works. It can be overcome, but takes a bit of effort.

I’ve heard the same from a diverse group. Nothing English-specific about it. The only way to learn the vowel quantities of a language is to actually learn the vowel quantities. If you spend a long time with a language without doing this, you won’t get them right. There is nothing surprising about that.