I hear you there, Steams multiplayer infrastructure is top notch, I’ve seen a few games get significantly clunkier when they added cross play and moved away from Steam’s services.
Steams also the leader in getting games to run on Linux, although between the heroic launcher or running the offline installers through Lutris, GoG isn’t that bad anymore.

I was questioning that myself.
So far digital goods haven’t been the subject of tariffs on either side.
It would also be hard to tariff successfully as it wouldn’t be difficult for Steam to setup something in another country’s Data center as "Steam International " to bypass any Tariffs.
Although this trade wars has prompted me to start buying games on GoG when that is an option.

Alcohol will be easy to replace but have a long term impact. Canada has had a growing micro-distillery industry for years now, pulling US liquor from shelves and the general increaseing “Buy Canada” intuitive creates a significant business opportunity for them. This will force people to switch from their usual drink, and once someone finds something else they like, it will be hard to court them back even after the trade war is done.