I hiked up Snowdon/Yr Wyddfa on a glorious sunny day a month ago, the first day the trains started running (they brought it forward a week due to the fine weather...)
I queued an hour for pics at the summit as one of the friends I went with wanted to, and I was happy to do it for somebody who had driven and then hiked hours to climb a mountain at my invitation. Honestly though, the rest of us wouldn't have bothered otherwise.
And yes, the reason it takes an hour is people faffing around taking pics for Instagram.
When I was on it fights and arguments started breaking out with runners in particular running up the final 10m of ascent which the trig is stuck on tapping it and running down.
Honestly, I thought it was ridiculous to get annoyed by somebody simply tapping a part of the mountain to say they had summited, and chose not to an hour onto their time because of vain faffers. I don't think that people wanting a picture at the trig trump people who just want to summit quickly and bugger off. I felt like outraged of Tunbridge wells stood in this queue, and the sheer lack of optimisation of the space at the top of the mountain by picture takers. Runners/more serious hikers weren't causing the issue imo.
The queue is not benign, it takes up a lot of space at the top of a mountain that potentially prevents people summiting, and everybody spending an extra hour at the top would only make the issue worse.
Disclaimer: When I'm not hiking I am a trail runner/Strava wanker.