Steele was shopping it around to media outlets extensively before the election, and Mother Jones reported on it on October 31, 2016:

https://www.motherjones.com/politics/2016/10/veteran-spy-gav...

Furthermore it was raw intelligence not meant for public consumption.

But wasn’t the Steele dossier used to get a FISA warrant to spy on the campaign, after the original request was denied?

Politicizing the intelligence apparatus would be highly disturbing, even moreso than when the Obama administration apparently used the IRS to target political opponents [1] like the tea party.

[1] https://en.m.wikipedia.org/wiki/IRS_targeting_controversy