I think it might be because of the ubiquity of music piracy during the 90's. In it's heyday, you could get anything off of Limewire, Kazaa, and of course Napster with extremely little effort.
By contrast, pirating video didn't come until later, when it was more technically feasible (downloading music over a modem already took forever, can you imagine downloading full length movies!?) and by that time, the likes of Spotify had already made legally consuming music so convenient as to make piracy obsolete.
Even now, the pirating of PC games is being made more common by the introduction of the Epic Store, which, regardless of your feelings on it, has added friction. Games promised to Steam users are being delayed or going full Epic exclusive and many users are saying "fuck that, we're not getting railroaded into using a launcher we didn't like" and turning to piracy instead.
The video landscape is even worse, where it used to be only a select few providers had their own bespoke services (like HBO) now every channel is looking to make their own damn subscription happen, which is adding tons of friction, causing the boom in piracy.
The music companies learned, and the video companies haven't, that the main way to counter piracy is to make the legal way to get something as easy as possible, so easy that customers don't mind parting with some cash. And streaming right now is anything but easy.