It certainly is a different ecosystem from when we joined (I, a little later than you), with more options now compared to then.

Regarding creating content, while posting may sometimes lead to blockages (there are more ways now to find inspiration), commenting doesn't really need much inspiration. Only paying attention to what you read and finding something to comment about, which is generally easier than writing your own post.

Now I have to try and build to 5m impressions all over again

That's probably not fun. Without being over that threshold for a long period of time, I see it like a constant struggle. Hope you make it!