DSS is similar, OP, when his dad's home – Xbox full-time.
When it's just me and him at home, though, he's usually used up his play time allowance for the day (DP works afternoons / evenings) and I've started to get him into other stuff.
Books (am I very old-school with this?) were my first go-to - after a few trips to the bookshop he's now found a series he's into and will read for an hour or so at a time.
Then we found some step-by-step manga drawing tutorials on YouTube and he spent hours following those and drawing along. I've now got him into working on his own comic book, creating backstories for his own characters. As long as I show lots of interest and excitement at regular intervals, he's quite happy drawing and putting it all together into storyboards. I got him a couple of cork boards for his room to stick them all up onto and move them around.
YouTube tutorials are actually pretty great for all kinds of stuff - chemistry experiments you can do with stuff around the house, how to build things...
Painting was another winner – a couple of big sheets of canvas outside and some chunky paintbrushes. He did a big painting of the world one of his Xbox games is set in, so that's up on his wall in his room now.
We've also recently got into a game where I give him a prompt word and sending him outside to find materials to make it with (an elephant, an alien, a hat). I'm still finding bits of stick and old leaves all around the house, but that's ok with me!
Training the dog to hit the deck when he pretends to shoot it was another hit –although she now does it whenever anyone points at anything–
It took a while for us to get to this point, though – I'm (again, perhaps, old-school) actually a massive cheerleader for boredom in kids. The first few months I gave DSS a couple of ideas and left him to do what he wanted with them. He didn't do much... until one day I was on the couch reading and he came and sat next to me with his book (with a GIANT huff - ha!), and the next day he picked up the sketchpad, and off we went.
Let him huff and puff and count and daydream if he wants – the other options are there. If he gets bored enough of being bored, he'll find something to do....