Yes they are all very valid points. I think the issue is that generally most vets aren't exotics trained so know very little at all about hamsters when it comes to what could go wrong. They are sadly seen as pets who don't live long, get stressed easily and "not much to be done" by some vets - just as by some parents! Which we know isn't the case - they could need dental work, surgery, pain relief, operations all sorts. Most vets will prescribe antibiotics and pain relief if they don't know what they issue is. And see if it gets better. Some will offer x rays or scans but they won't always show what the issue is with illness.
However any emergency type thing is usually treated well - eg an eye that needs removing or a broken leg. Diseases, less is known about and diagnostics are limited. For example most vets can't categorically diagnose Cushings disease. The only way to categorically diagnose it (and rule out other possibilities) is via a blood test. Hamsters veins are too small to take blood from. There are a few rare vets who can get blood from a hamster's ear but most will say it isn't possible. Cushings isn't that common but it's sometimes diagnosed as Cushings when it isn't.
The main issue there, and which partly creates that view, is that there is literally no licensed medication for hamsters! It is at the discretion of the vet whether to adapt cat or dog medication, and thankfully most vets are happy to do that and want to prevent suffering.
I think the very least the medication manufacturers could do is add hamster dosage to medication for cats and dogs (for a hamster, it doesn't just go by weight - their metabolism has to be factored in).
Although hamsters aren't technically exotic pets, the difference is that an exotic vet does more hamsters specific training. A general vet will probably tell you they hardly have any training at all when it comes to hamsters - as part of their studies.
