Luxon author here. Obviously I (and many others!) put a lot into Luxon, but only because it seemed so useful. Now that it's hopefully becoming obsolete, I get to look at it fondly as a nice bridge to the future, and I appreciate all the love it's gotten. All things end.

I spent a day fighting with date-fns trying to get some date calculations working and was to the point I was questioning if my entire approach was flawed because there was no reason I should be spending that much time figuring our some simple date calculations. Eventually I decided to try swapping to Luxon. 30 minutes later and it was all working.

I'm still guessing I misunderstood something fundamental about date-fns, but for now I'm advocating for Luxon.

Another way of viewing this would be that these and other implementations have paved the way for standardization, which would possibly never have happened without them.

IIRC Luxon doesn't have the concept of Calendar/Naive date/time, which is one of the major improvements brought by Temporal for me