I fully believe that the line to get into the lounge was 30 minutes, but it is also very likely that the lounge was empty. Like so many things with the world's "biggest" airport (maybe one day when they have 6 runways), this lounge was made to make claims, but not really be that good in any particular way, shape or form. The entry system is an absolute joke, They have stations for maybe 7 agents to check people into the lounge, but I have never seen more than 4 working at one time. The queue on the left for people actually invited by their airline is badly sign posted and rarely policed, meaning that what should be the primary people/purpose of the lounge is often an after thought. As also mentioned above despite having turnstiles with scanner technology these do not work for anyone without being validated by an agent (except IGA pass holders). Meanwhile, if you are trying to use the lounge because of status, and heaven help you if it is alliance status, they do not seem to have much in terms of reference material, so if you are flying BA in Y, but are Emerald on any other Oneworld carrier, count on 5 minutes to sort that out, at least. As the lounge primarily services the flotsam of international aviation (BA, QR and EK are perhaps the best airlines using the IGA lounge) While Skyteam members are currently using IGA due to the Skyteam lounge fire, All Star Alliance carriers use the TK lounge, so the vast majority of passengers using the IGA lounge are from the likes of Uzbekistan Airlines, Iran Air, Air Montenegro, and of course the well named SCAT airways, and such passengers seem duly impressed with IGA. Then of course as mentioned before there are all the lounge program and credit card programs, which seem to be the priority for the IGA staff.
Regarding the comment about "compared to the United States" what kind of comparison is that? There are many terrible lounges in United States and there are some great ones. While most of the big 3 lounges were mediocre at best a decade ago, I can say that now most DL, AA and UA lounges are pretty good, as are most of the bank associated lounges, such as Centurian, Cap One, etc. I'd say that after upping their game, most European lounges are still pretty mediocre even at their hubs. I do not know how you can call IGA "solid". The general experience as you pointed out is a long wait to enter with often incompetent agents. BAsic and terrible food, which is never quickly replaced. "Freshly cooked" food, which is impossible to get, broken fridges tepid drinks and lack of ice (for FIVE YEARS)! Often lack of cutlery or plates. I mean maybe you got it on a good day, and there were forks available (they do not seem to be able to ever keep up with stocking clean forks especially). I mean if someones standard was a Delta CIN lounge from 5 years ago, a third party lounge at Lyon or something then fine, but when one considers that this thing is less than 5 years old, had a two year break and is part of the company that brags about building the World's biggest and best everything, then it is garbage. Oh, and BTW yes I have spoken with management, IGA, BAT and now TRU. IGA says that the lounge is wonderful, of course they do, they love to talk about SKYTRAX too. BATS officially would say that all was wonderful, but off the record that their budgets were cut and that they were going to lose the contract anyway. TRU people talk about how they know that BAT ran it down, that they will improve everything, but off the record complain about the state of the equipment and their lack of budget, and seem to have been struggling to even launch their own webpage/site for perhaps a year now - not surprising as the company was seemingly founded solely to take over running this particular lounge at an even cheaper price.