The rule doesn't even matter in these cases. I had a sanctioned singles round a few weekends ago that was a killer in this regard. We had a 4-some. I played with one of my best friends, a second guy I get on well with, and a player with a reputation for being slow. The guy with the reputation for being slow was... fine. He used all of his 30 seconds. Maybe he even exceeded it at some points but it wasn't worth putting a clock to for sanctioned league.
Or at least it wouldn't have been if not for the other two. By the time we got through our third or fourth hole they were in my ear about it. I finally snapped back at one of them about 8 holes in that "I don't give a ****, I'm not playing well enough to pay attention to anything but my own play" after he moaned at me that it was literally "the slowest round of [his] life."
The guy was not that bad, but his rep was just instantly the first thing in their minds.
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Side story, related to 'that guy' because it's funny in how ridiculous it is. Same round, late, 3 holes to go. I'm over my lie grumbling to myself about how I wish I'd been 10 ft further back. That dude starts talking to me *after I've approached my lie* trying to convince me to throw a sidearm. I told him to shut up and let me throw my shot. After botching my shot I approached him, apologized for snapping at him, and just asked that as soon as he sees me approach my lie - I'm not interested in anything but focusing on my shot. Literally 2 holes later as I approach a birdie putt from 20ish, I just get my foot down behind my mini when he approaches from behind and juts his putter in my face "Hey man look we're twins! I have the same disc!" (as the disc I'd just drove) I just looked at him and said "I do not care about your disc when I'm trying to putt."
*facepalm*