I have noticed an increase in being turned away with Lounge Key, which I do get through my bank. I would say the lounges have been busy but not enough for there to be a space or capacity issue and most rarely stay for the full three hours. Admittedly I am often a solo traveller and I suspect lounges are prioritising groups, rather than discriminating on other factors.

I just tried to pre book for a trip to Oslo in Feb from Gatwick South to avoid being turned away. Only one lounge let me book but it is a pretty poor service, I might as well book directly without using my lounge key.