My father (who is of the same political leaning as you) was one of the most experienced traffic officers in swp during the 80's, 90's and 00's. He disagrees with this blanket ban as he attended VERY FEW fatalities in 30 mph areas (which were not caused by speeders).
The senedd debated a petition where they asked the creator to stop as it had reached the threshold. They then totally dismissed it without any real debate. There was even an earlier review put out by labour themselves, to about six thousand people where the results came back as 65% against. A senedd member (can't remember who) dismissed this as non-representative; their own poll!
The new petition is now above 325,000 signatures. There's probably not that many Tories in the whole of Wales, so some other party supporters must be voting, like all of my colleagues in Llanelli who are dyed in the wool labour voters.