They are burning a lot of money quickly but that is not the biggest problem. This is most worrying about Snap:

Daily active users 178M (est: 180.5M)

Their active users growth is very slow.

166 (Q1) -> 173 (Q2) -> 178 (Q3)

It seems that already slow growth is slowing down even more. They started the year with 5% quarterly growth, then went down to 4% and now barely 3%.