I think the "I don't want xyz, just fix the bugs!" comments are as predictable as the claims that Apple is working on emojis instead of fixing bugs, when we all know the unicode consortium decides on emojis and it has absolutely nothing to do with iOS engineers fixing bugs. But people here love repeating that clichéd comment anyway. Since neither you nor I know the specifics of the 18.3.2 release we don't know what it contains, and we can't accurately speak to whether it is a "mass bug fix release" or not.
If Apple were to delay a bug fix/security release in order to make it somehow larger or more significant, then they would rightly be criticized by people who ask why Apple didn't release some of those fixes and patches sooner, when they were first ready. If they do a series of smaller releases as soon as fixes and patches are ready, then the same people complain that the fixes aren't significant enough.