Except that it did.
Eight Tejas flew 6 sorties a day each and had a 100% serviceability during Gagan Shakti.
And if by "factory level technicians" you mean the HAL logistics support team during the Gagan Shakti excercise then you are being blatantly disingenuous; it is standard practice for IAF if not for every other airforce in the world to use engineers and technicians of the respective production companies during large scale excercises and especially during war to help with maintenance and logistics.
HAL technicians and engineers were crucial during IAF operations in Kargil in 1999.
Here's the thing, what IAF wanted by the 2000s was a Gripen-E type fighter and they aren't getting that before the Tejas has the chance to better itself through Mk1s and Mk1As, even the Gripen had to go through A, B, C & D versions to get to NG and E.
The above doesn't mean the current Tejas can't be compared to JF-17, it just means that the future version of Tejas can't be compared to JF-17 as it will be far better.
And if IAF truly wasn't happy with the Tejas they wouldn't have committed to 324 of it.
https://quwa.org/2018/03/20/indian-air-force-commits-to-procure-a-total-of-324-hal-tejas-fighters/