Same where I live. Roundabouts have worked well and efficiently for years. People obviously have to use their brains and judgements and, miraculously, it works, day in and day out!
I have experienced the same at signalled crossroads. When the lights stop working people have to neogitate it together, moving carefully watching the other drivers, and it seems to work, and is arguably more efficient and safer. When there are lights, people go mad trying to make it through before red and assume safety is taken care of.
Back to roundabouts, the problem with them is that there's no money in it for contractors, maintenance companies, consultants. No complexity. Just a load of earth with a kerb around it. Needs mowing sometimes. I think this is the issue, combined with an extreme health and safety regime.
We now have this absolute monstrosity near us, called a "hamburger" interchange. It is basically a butchered, segmented roundabout with about 50 traffic lights around it. You move from section to section, waiting and waiting. If you can get through before they change, go for it, because you'll have a long wait otherwise. It all looks very complicated and expensive, and it isn't very good.
Then again, we see this with works traffic lights. One near us last year, on a straight road with clear visibility both ways for a 2.5m length of "works". Absolutely no need for lights. Waste of tax payer's money, control freakary, and a waste of everybody's time.