it kind of sucks to make shinies as rare as they are, especially when half of them are very easy to miss now
i play through entire games, taking my time, and usually see... zero. in arceus and violet that number has increased to two, and i bent my team around them when possible
but they are mostly experienced if you finish the game, read a guide, and tediously grind 5 mechanics to bump the odds up until you find a specific one, so that you can put it in a box and try for another
i own a pokédex website and i couldn't tell you what more than a handful of them even look like
crank that up to 1 in 1000 man, maybe more
@eevee i think it was neat to have absurd rarity when the internet wasn't as much of a thing because it could generate urban legends
but adding levers you can pull to make them more common really pushed them from cool video game cryptozoology to A System For You To Grind