US based optometrists are licensed medical providers, credentialed to diagnose and treat eye disease, including prescriptions for controlled substances. They are sometimes covered by medical insurance. The major scope of practice difference is that optometrists generally may not perform invasive surgery (though there are a few states that do allow optometrists to perform LASIK or post-cataract surgery laser procedures).
There are plenty of optometrists who work in glasses/contact lens shops and that’s all they do. I wouldn’t trust them to treat eye medical issues, at the very least because that’s not what they commonly do all day. Larger optometry groups or optometrists that work in an ophthalmology group are more suited to disease care.
Ophthalmologists do have more training (they are medical doctors first with a 3-4 year eye specialty and sometimes a 1-2 year Fellowship training for subspecialists).
Oh I know, let’s add more lanes and car traffic flow controls. That’s proven successful