This card is kinda bad. Compare to Exchange of Information. EoI allows you to make the Runner lose 2 points so that you gain 2, and if you gave the Runner 15 Minutes, then you can also make the Runner lose another point on top of that. Backroom Machinations costs 2 more credits than EoI's 0 credits, and also removes the tags. Simplifying things, Backroom is at most 25% the value of EoI.
So yeah, this card sucks. However, you don't have EoI anymore, so maybe you're so desperate for single tag punishment that you play this. Alternatively, you can also opt to not play any single tag punishment at all, which, in my opinion, is the route you want to be taking. In general, the three NISEI-original tag punishment cards are extremely lackluster, so you should think twice about putting any of them in your deck.