Wow, I used to work in the security game myself many years ago. As I was leaving we were just starting installing multiplexed cctv over fibre, predating the whole ip camera thing. It was one of those games that if you stand still for too long you end up behind the curve.
I’ve come at things in the complete opposite direction to you! Electrician then service engineer then into something completely different, all the while doing my own diy electronics stuff but never touching software. I’ve been slowly teaching myself PIC programming and, as you point out my electronics background has really helped. Sometimes it does feel like two steps forward and one step back tho. I need to knuckle down with it a bit more but other interests get in the way and I get distracted from the software thing.