I can totally relate here. I remember that when I started running, "it's too cold", "it's too windy", "it's too dark", etc. were real issues. It was too dark and I didn't had enough experience running in the dark, and for me it was indeed too cold. If one can afford the equipment, good equipment does reduce many issues and if that means that you'll go running more for me it was money well spent.
After a few years as I had more experience, ran faster (and warmer), these issues mostly disappeared. Nowadays on winter I only run with shorts, a thin hard-shell, and thin shoes (sometimes five-fingers) with temps of -5C. Some days get much colder (e.g. -10 or -15 C) but when I've used some of the warm clothes I used in the first couple of years of running they've always felt too warm. The only thing that's still an issue is running in the dark. Independently of whether I know the trail, have a head-lamp, etc. I run slower in the dark than during the day, except on the track. So now when its dark, I always go to a running track to run. Most of them have lights on till late, and some schools, most universities, etc. have one and they let you use it for free.
Cold tolerance seems like a very individual thing. I've been up and down the scale a few times in terms of my weight, condition and speed. It doesn't seem to have made much difference to my comfort levels in the cold. I think the coldest run I've done in regular shorts/shirt/shoes was exactly freezing. Even then I wore a thin beanie and gloves. Without those, I would certainly have been quite uncomfortable and might have been at risk for worse. Hypothermia is a real thing. I've seen it, and don't want to experience it.
I guess it would be nice if I could run wearing less, but I honestly don't think it would be safe for me. Your mileage obviously does vary. ;) As it is, I have winter shirts, undershirts, and socks that are all different brands, and I am keenly aware of which ones are better at which temperatures. There's a bit of an art to wearing exactly the right level of gear for the conditions, and I've simply had to become good at it.
After a few years as I had more experience, ran faster (and warmer), these issues mostly disappeared. Nowadays on winter I only run with shorts, a thin hard-shell, and thin shoes (sometimes five-fingers) with temps of -5C. Some days get much colder (e.g. -10 or -15 C) but when I've used some of the warm clothes I used in the first couple of years of running they've always felt too warm. The only thing that's still an issue is running in the dark. Independently of whether I know the trail, have a head-lamp, etc. I run slower in the dark than during the day, except on the track. So now when its dark, I always go to a running track to run. Most of them have lights on till late, and some schools, most universities, etc. have one and they let you use it for free.