This is a very long Thread, but I've noticed a number of "my 5000TL's" don't hold air.

I have used 5000TL's (and other tubeless tires) without issue, but some 5000TL's seep A LOT of air through the sidewalls - some so much that they are unusable (as tubeless). I have one, manufactured in 2021 code 249404 like that. After repeated attempts at installing it (using 30-40ml of well shaken'd Muc-Off, low pressure, high pressure, sitting overnight, etc.), I finally gave up, put it underwater in my pool, and was shocked how permeable the sidewalls were!