NVidia is not 5 years ahead. Google has been using their own designs for years now, they just did it quietly and only now opened up their hardware to third party users. Their performance for AI is at least equal to the NVidia offers.
Microsoft is using custom designs too but they are even more secretive about it so it's next to impossible to get solid information on what exactly is going on there and how they perform.
If you just look at compute (16 and more importantly 8 bit for ai) performance even amd is entering with specialized chips derived from their gpu devision and while their gpu's are less than stellar for gaming, their chip-design is more than a match to NVidia in raw compute, which is where it counts for AI.
NVidia was the one on the marketing drum the most, pushing products to the open market, but they are not ahead technology wise in any significant way compared to the other players, they are just louder (as usual).