Learn Turkish: Dün sokakta beni kırıcı olacak kadar tanımazlıktan geldin. - Yesterday on the street, you pretended not to recognize me to a hurtful degree.

This uses the structure from your current lesson: the verb root tanı (recognize) + the negative aorist suffix -maz + the noun-making suffix -lık + the ablative suffix -tan, all followed by the conjugated verb geldin (you came). Literally, it translates to "you came from a state of not recognizing." This is the standard Turkish idiom for feigning ignorance or pretending not to do something.

Why is the object beni (me) in the accusative case here when the main verb is gelmek?

Even though the final verb in the sentence is gelmek (which usually takes the dative case for direction), the object beni is actually governed by the verb root inside the idiom: tanımak (to recognize). Because you recognize a specific direct object, tanımak requires the accusative case (beni).

How does the phrase kırıcı olacak kadar work here?

Kırıcı means "hurtful" (from kırmak, to break), olacak is the future participle of olmak (to be), and kadar means "as much as" or "until." The pattern [adjective] olacak kadar is a common way to say "to the point that it would be [adjective]" or "enough to be [adjective]." So literally, it means "as much as it will be hurtful."

Could I use instead of in this sentence?