Mr. Steele was working as a private citizen not as an MI6 agent...unlike the Russians who were very likely members of the FSB, the GRU, or closely connected to the Putin government!!!

a) You don't actually know that Putin didn't send those spies to talk to Steele, and you definitely don't have proof they're all dead,
b) You can't prove that Russia wants to weaken the US,
c) The reason that Putin wanted Trump as POTUS is because he said he wanted relations with Russia to return to 'normal', not to 'harm' the US.

Have to remember that it's axiomatic to these people that Trump being POTUS is 'great for the USA' and that EVERYTHING Obama did ... sucks. Which, by definition, includes sanctioning Russia. Ergo, Trump getting rid of sanctions Obama put in place must be, in fact, great for the USA. And if Russia wanted Trump, like they did, then Russia must be 'good'.

I've already made these arguments to these people, many times. You'll get nowhere, trust me. They believe (or will claim to until the bitter end) that what Trump did is the same as what Hillary/Steele did, and there's no getting them to see otherwise, logic/common sense notwithstanding.

in Republican world, if Trump was bad for accepting help from Russia, Hillary was bad for accepting help from Steele.

Yes, I know the UK is an ally and that it wasn't direct help from Steele, who provided the info the Fusion GPS. The differences are lost on Republicans.

An American company that was hired by a republican to do opposition on trump. GPS in turn hired Steele to investigate trump and his overseas connections. After trump won the primary the republican called off the investigation. The Clinton campaign continued to fund the investigation. Somehow the Steele dossier got into the hands of McCain. He turned it over to the FBI, at Graham's urging.