I saw his skin from really close up, and I tell you, that's not the foundation. He had very light makeup on, pores were visible, and his skin was clear and smooth. I bet he uses the type of cosmetic procedures Korean stars also do, you need to take care of your skin.
Some of the celebrities in Asia have 15-17 step skin maintenance routines DAILY. (and I tell you, they do work, I only use 4 steps myself, with Korean products and my skin conditions have never been better! And previously I was going from dermatologist to dermatologist begging for help with rashes... Asian skin products are amazing).
There are actually hand products (moisturizing gloves, similar to facial masks) that plump up your skin on your hands. They are amazing
Lots of internal hydration is important, too. And let's not forget that he exercises daily, even now when he is restricted because of his operation, he still exercises daily (I overheard an assistant mentioning he got his own gym in the hotel room
) . Regular exercise improves blood flow, which in turn improves your skin condition, too.
All in all, i think his secret is that he pays attention to his health (apart from his suicidal drumming style and not wanting to rest), he eats healthy, drinks red wine in moderation (that has a bunch of health benefits), has some kind of cosmetic facial routine, exercises every day, and from time to time he has some botox here and there
Or maybe he simply is really a vampire, who knows?