There’s a term for that, I think, such as substituting “d” in place of “t” is called “t-flapping”. Damping or muting, maybe.

Checked with quora and they say it’s T-glottalization, where the "t" is replaced by a glottal stop (the hitch in the back of your throat when saying “uh oh”, for example), and apocope or deletion, where the sound is omitted entirely.