FFHKG,
I notice you are comparing MAN T3 to the following airports as a comparisons:
LHR T5:
A new build terminal, purpose built for the needs it is serving today, where its sole users are BA and the occasional IB flights.
Now, aside from the fact the security area was purpose built to handle the volume of passengers it does, You are ommitting one big variable. BA is a full service airline where the vast majority of passengers have checked baggage included. This means much less crap in their hand luggage.
T3's main tenant, and indeed is MAN's biggest tenant is Ryanair. The airline where bags are 'optional extras' to which people do not want to pay to use. This means the pack their whole f*%king world into their hand luggage. Kettles, Irons, large liquids, hair straighteners etc. 2 days ago through T3, lane 5, I saw an African gentleman with a huge car wing mirror with integral lights in his hand luggage (and no, I am not joking in the slightest!). I can guarantee you now after 300+ visits to both airports, Heathrow T5 does not experience the same hand luggage issues as MAN T3. It's absalutely pointless comparing the 2, you couldn't get 2 more polar opposite passenger profiles of you tried. When you have a flight that leaves around the same time that the 10 based Ryanair and 4 away based flights go off together, then quite frankly, 30 minutes is f*%king incredible considering. It wouldn't matter how much staff you throw at the situation, it wouldn't stop people's randomness and stupidity,
You also compare MAN against VLC, which is an airport well less than half the size of MAN, so, I would expect to get through there faster by economy of scale.
Then to ICN/HKG/KUL etc. These are worlds away from any UK airport by design and scale, so again, it's pointless to compare. They have much more resource to throw at airport function than the UK does, so, I would be gravely concerned if they had major issues with queues.
Now, you can call this jumping at MAN's defence for 'mediocre service', but, unless you look at the bigger picture and look at it subjectively, it's hard to judge confidently. If that makes me a 'blind MAN fan' then so be it. I too have travelled very extensively around the world, and while I agree MAN has its shortcomings and far from perfect, it's certainly not one of the worst in the world, not by a very very long shot. If people do think MAN is one of the worst, then all I can say is they have had some very sheltered travels.