I changed over a few months ago, and it was a bit of a holy shit moment. Can't rule out that the tyres themselves are just better or the very low pressure just improved the bike feel, but the grip and comfort was a different world. One chuck-in-a-tube flat in the last 3 months and otherwise it's incredible and I am never going back. Best bike upgrade I've done in years.
That said, road tubeless is a bit of a scam - from what I've heard, a flat will leak down to a barely rideable level and you can't use a CO2 cartridge if you're in a hurry to get to work or something, and that's about the only circumstance you'll really care about pinch flat resistance. The maintenance hassles of clearing out your tyres with old sealant are significant, and apart from weekly lube and tyre inflation my roadie doesn't get that much love. Similar hassles apply for mountain bikes, so I can see why people who like their bikes to just be ready to ride on a weekend without too much futzing around are not converting.