I agree and respectfully would like to point out the role other nations played in designing and helping India with everything from the engine , avionics to cockpit displays etc.
This is not some e-bike assembling that we are talking about. Think about it for a minute; a COUNTRY X, with colonial past and a socialist economy that is in doldrums after USSR's collapse. There was no liberalization and there are projects to be funded with very limited pool of talent and limited skills.
Do you really think design consultants would give you every single formula? These companies were also themselves manufacturers. Why would they give their best recipe to us for just a consulting fees? Also, the second aspect of design consulting is the ability to absorb that knowledge and replicate it in a result-oriented manner. Every country goes through this, including China.
Euro fighter took 11 years from conception to the first flight. Rafael evolved from Mirage 2000 into Mirage 4000 and finally into Rafael. French were smart and used the basic design and know how from Mirage series to build a good plane. Similarly JF17 can be argued to have used good basic design to be made into what it is today.
Yes, with 4 master countries with strong aerospace industries, plethora of aviation experience, money, power and availability of talent.... sure. Typhoon took 11 years from the stage they started actually doing something. The program started in 1983 with tonnes of political discussions, design concepts, debates, egos, etc. The same crap was happening in India as well. And then throughout the 90s, our economy was trying to shift from command economy to free market after USSR's collapse. Those were tough times - project had to be shelved. By the logic you are giving here, Tejas took only 15 years till LSP stage from 2001 to 2016.
However for what ever reason Indians chose to reinvent wheel and went the way which should have been a success considering how much help they had available from foreign countries but instead ended up with a plane which is to risky to fly over Delhi.
Please see my first point about how design consulting is done and what are the things that are given out. There are two challenges here: 1) How much the consulting company (themselves a manufacturer) gives away, and 2) how much the client country has the ability to absorb and how fast.
39 years on and Tejas is not trusted to fly over our heads.
Yes, that's why they were sent in 3 countries and is competing in 2 more in tenders giving flight demos, isn't it? The simple reason why they blocked all single-engine jets is due to perhaps internal politics. You see, Air Force pilots have a lot of pride in their squadrons and machines. Imagine the political egos of wing commanders hurt when they say "MiG-21 and Mirage 2000s cannot fly but Tejas can fly".
Tejas has over 10,000 hours logged and not a single crash has happened. And no, they cannot hide stuff like that unlike China here. As you would know here in PDF, most of Indian stuff is just openly available.
So your guess (apart from the disregard generally shown by Pakistanis on any technical points) is as good as mine.