People such as yourself don't even really comprehend exactly what the Steele dossier was. The dossier was actually a series of reports—16 in all—that total 35 pages. It was written in 2016, and it's a collection of raw intelligence. Steele neither evaluated nor synthesized the intelligence. He neither made nor rendered bottom-line judgments. The dossier is, quite simply and by design, raw reporting, not a finished intelligence product.
Christopher Steele recorded what he was told by witnesses during investigations. This is exactly what a MI6 British intelligence agent has been trained to do. The substance of these memorandum can be true or false, but the recording of information is (or should be) accurate. In that sense, notes taken by a special agent have much in common with the notes that a journalist might take while covering a story—the substance of those notes could be true or false, depending on what the source tells the journalist, but the transcription should be accurate.
Witch-hunting the dossier is the only thread left that the right has to pull on, so they'll do that. That's fine, that's their right. It's going to be a big waste of taxpayer money because it's already been scrutinized and dissected many times by many Republicans including the sycophantic, rabid Freedom Caucus Senators. The dossier has held up well over time, and none of it has been disproved.
