Seems that you might be unfamiliar with modular synths, which is what you see in the vid — although that's a software synth, because real hardware ones are messy and expensive (and require patching the cables and twiddling the knobs the same way again to recreate a previous sound). Modular synths aren't new, they were around since the sixties, starting with the famous Moog — although they declined in popularity in the seventies. The Eurorack standard was developed in 1995, and is the most widespread one. There's been somewhat of a resurgence in recent-ish years, from what I understand.

Look up 'modular synth' on Youtube, there are more than a few vids showcasing the workings. Some people do live performances with smaller-size setups.

The VCV Rack software, shown in the OP vid, is free and open-source, you can install it yourself and fiddle around with the sounds. Also e.g. the tracker/synth SunVox, available on phones (but desktops too) has a modular-ish synth as one of its parts.

I would say, however, that the composition here rather harkens to the old avantgarde-electronic composers. Sorta on the minimal side with instruments fading in and out, resembles 70s-80s atmospheric soundtracks for gloomy films.