It's POSSIBLE that the adjusters could take the rest of the slack out of it, and that the engine will soldier on for many miles.
I love reading about folks replacing their lifters because they were ticking. Unless the slop was from worn lifter faces or there was garbage in the lifters, they're just wasting time.
The vast majority of the time the tapping is from a lack of pressure at the lifters. The lack of pressure there is from excessive bearing clearances somewhere. Folks are lazy and don't want to go the full distance to fix a problem correctly.
I wouldn't even be surprised if the 4.0 worn rockers thing is the symptom, not the cause......and worn bearings started the whole fiasco.
The folks that replace lifters or rockers, etc, most of them probably never mention down the road that the engine blew up because it had oil pressure problems. Because that would prove they were wrong all along.