I have found the singleton and memorized way more intuitive on how to use. like it also as for our team we have some general library/package code that helps users make/use common resources like database connections, etc (which make use of singleton) and users can just worry about for their dashboards dealing with the simpler caching via memorize.
I think one thing in docs that could be even clearer is at what level caching is namely comments like in Expiring the experimental_singleton cache at regular intervals - #6 by ksdaftari could be just made even clearer on that singleton/memorize global caches (not specific to user like session_state). unless I am misunderstanding docs here (I say this as know have to train some of people making dashboards to be careful when actually cache especially if output that could be different for users, eg would be if hitting api that could have differing authorization depending on user).