Quite frankly Doklam & Galwan notwithstanding , when was the AMCA expected to enter service even if we consider the Mk-1 version ? It certainly wasn't expected before the end of this decade by the most optimistic amongst us regardless of what the government & the various agencies said or sources quoted by defence journalists.
As far as the LCA Mk-2 is concerned , it was supposed to go into mfg as per the plans frozen during MP's tenure as Raksha Mantri in 2016 by 2026. We aren't meeting that schedule now. It's out of the question. But AMCA , Ghatak etc were always due in the 2030s.
That's why the MRFA especially the Rafales are so important. And my gut feeling is 2-4 squadrons of Su-57 with the Item 30 TF before the end of this decade although all evidence of that happening seems loaded against such an eventuality.
If somehow Modi govt approves and releases funds for AMCA in 2024, by the history of R&D in DRDO/India, I can say, first flight by 2029 (+5 years from now) in induction by 2041 (+ 12 yeafs from first flight). By that time everyone will have 6th gen in arsenal.
India being one of the largest economies in the world by that time, will also have one of the low tech forces. Thanks to horrible decision making and no ownership by the top leaders.
Mark my word, India will ultimately buy F-35, sooner or later. PAK FA chanches are less as India did mot buy a new Russian aircraft since it got taste of American weapons like C-130J, C-17, Apache or Chinook. We will remain as a client state dependent on Washington, Paris or Moscow.
There are R&D delays as we are not industrial powerhouse like US/China/Germany etc but what least the govt can do is proper project audit by private party and timely release of fund may be in advance.