Why isn’t the Destination Thailand Visa a good fit? 5 year validity. Apply through soft power - simply a letter from a doctor stating you have a follow up appointment will do - even a dentist follow up
one has nothing to do with the other. OP is complaining about Penang embassy requirements which are very different (and easier) in different locations.
US tourist visas are hard because 1) usually is people with lower economic power potentially using it to illegally stay in the US and 2) at least is a lot more consistent across different countries.