Historically we've been bad in December so there's a lot to overcome.
I know this is the meme, but here's MIA's December record over the past 4 years:
2023: 3-2
2022: 0-4 (fair enough)
2021: 3-0
2020: 3-1
The two years MIA didn't make the playoffs, they played quite well in December. And even the 0-4 in 2022 wasn't a cold weather thing: they lost @SF, @LAC, and home against GB, with the only cold game being the snowball game in BUF.
The game against TEN last stands out as the kind of "December collapse" the meme is famous for, and I guess you might also count getting blown out by BAL. But there really isn't much meat on the "MIA can't play in the December cold" bone.