I thought it had to be both, not either or. I mean, you couldn't have a large avatar just because it was under 41KB. My current avatar was originally png, but I wasn't allowed to use it because of a huge filesize. Saving it as jpg fixed that, and it was the same dimensions. So yeah, it has to be both.
...Oh I see, the wording is a bit confusing. It says "whichever is smaller", so even if it is 130x130 or less, it doesn't matter if it has a huge filesize, as anigifs tend to.
(It's a pretty cool avatar, anyway)
RIP Slowpoke Jackson