Deterministic password function

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By what factor is a keyspace reduced by using a pre defined amount of ascii character types vs filtering input data directly through tr?

Is it negligible?

pseudo-code examples (assuming each group of 4 bytes are filtered from a well stretched KDF):

$(4 uppercase | 4 lowercase | 4 ascii (non-alphanumeric) | 4 digits) -> shuffle chars using fixed binary seed

$(1000 byte binary input) -> filter non ascii bytes -> trim to 16 bytes