I agree, Indian ATC is among the worst. This is coming from a pilot who has operated commercial flights into and out of over 100 countries.
To be fair, the controllers there are hamstrung by their inept gov't bureaucrat higher-ups who limit the tools they have to ply their trade.
But at the same time, I have seen plenty of downright arrogant and unprofessional behavior many times out of Indian ATC.
I'm sure my commentary will piss off many Indian nationals but you guys really need to get out and fly the world to see what I am referring to. If you make it a national pride issue, the system will never change.
Anecdotally, I recall one time on approach into BOM. There was an aircraft a few miles ahead us. The TCAS blip was right on the 5mi ring so I couldn't tell exactly how close he was but spacing seemed less than 5 mi. As we started to get rocked by what appeared to be wake turbulence, I asked my FO to query ATC as to type of aircraft, the plan being if it was a heavy I would slow up to final approach speed thereby getting out of his wake. He made 2 requests to ATC, no reply. After making a 3rd attempt, the controller came on the radio: "why do you ask such frivolous questions? Spacing is more than adequate. You waste my time with such frivolous inquires... blah, blah, blah". The lecture went on for what seemed like a minute (an eternity in ATC RT time). All the guy had to say was type of aircraft and the discussion would have been finished. I told the FO, "I have the radio". I then proceeded to tell the controller, "If I ask what I am following you will tell me. Got it?" Then before he could reply I switched to tower. Upon landing, I contacted our operations duty manager and told him I want to file a report on this guy. He took me into an office and asked if I would speak to the controller directly by phone. I did, we tussled back and forth, and in the end my point was made and accepted... that we are in a dynamic environment as pilots, if we're getting rocked by wake of a heavy (it was a B744 ahead of us), then we must take action to slow up our speed so as not to exacerbate the situation. Instead of his arguing about it and wasting ATC air time, he should have answered me with one word, (B747-400). His excuse was that he was training and that he did not have time for such questions. Well, I'm a trainer too. If you're not up to the elevated tasks and stresses of being an instructor, then you're not cut out for it. It's that simple. He piped down from there and apologized.
I witnessed a lot of this type of behavior by ATC, between them and other pilots. Part of the problem is that Indian aviation is growing faster than existing infrastructure improvements can keep up. But the other part of the problem is systemic, in that an approach of nationalistic pride limits the process of self critique for the purposes of improvement overall. A growing nation should always be weary of this