I think the introduction of these winter spike tyres make a huge difference.
I'll outline my commuting over the years.
As a youngster I'd ride to work when I could - we did car sharing stuff, and it was only 6 miles (mid-late 80's - big company so most lived local). Got moved about a bit, then got a job that was 20 miles away. I was early 20's and racing, so this was great training. If the weather was not so great, then I took the car (lazy), but I averaged 3 days a week commute (120 base miles), plus 2 days weekends racing TT's (which is alot for a youngster). In winter I used to take the MTB (which is the same machine I have now) but I but on a dynamo at first with battery lights. Then cam BLT from canada with bid lead acid batteries and 3w of halogen lights... (crap compared to now) but at £100 15 years ago these were the danglies.
I'd ridden through winter, cold/frost etc, but I don't think we had that many wet winters. The last two days remind me of back in the late 90's - cold but dry, no bad ice. I used to love riding through frosty roads n 20mm tyres (non of this 23mm stuff).
What changed my mind about winter riding was a morning where there had been a late freeze - i.e. 4-5am. My MTB was all over the place 4-5 miles in, then was fine. After the 10-20 mile route I came off 3 times - no 1 was at 20 plus mph, and just on the road - I was battered and bruised by the time I got to work. What got me, was my boss fell off at home in the ice before he had got more than a mile - he was off for months... I'm now his age.
That day's ride changed my young head about ice ! I stopped riding in ice, until the spike tyres came out. I bought mine 2 years ago. I commute all year round, so this means I don't stop that with my old trusty MTB with ICE spikes.
I will not get my road bikes out for a spin at weekends if the weather is icy - not worth it - the bikes are vintage and very hard to replace parts.
So, the lesson is, if you want to ride all year round, get spikey tyres - unless you are less than 25 and still really bounce. I bounced at 38, but my shoulder didn't.