I just replaced mine yesterday - pretty easy job and the second time I've done it. 3rd time altogether as mobile service did the first. That's over 2 years and approx. 20K miles. Used these:My Y had this issue a few weeks after delivery, at the beginning of summer '21. I was a new owner at the time and didn't have the luxury of knowing about these posts in TMC. As OP mentioned, the problem always goes away after a few minutes of full blast so it wasn't as annoying as could've been. I lived with it for the summer, and then the dry FL winter made the issue go away. That, was just a temporary reprieve as the smell has returned along with summer and humidity.
I scheduled a service appointment for it and was promptly given a cost estimate of $144 ($140 for the cabin filter replacement and the rest tax). I know some folks got their filters replaced at no cost (probably in the Model 3 threads), but I doubt I'll have similar luck. Will know either way tomorrow when mobile service gets here.
XTechnor Tesla Model 3 Model Y Air Filter HEPA 2 Pack with Activated Carbon Tesla Air Conditional Replacement Cabin Air Filter
Lubegard 96030 Kool-It Evaporator and Heater Foam Cleaner
Cost $68.90 w/ tax and took about 30 - 45 minutes altogether with 15 minutes for the cleaner to work and running the fan for 5 minutes afterward. There are easy Youtube instructions and the tools come with the filters. If your a little handy it's a fairly easy task.