Honestly, if there's a quality problem, then it should be admitted as such. It's fine, lol. No need to cope with whataboutism or deflection or whatever.
Given the PLA's development in recent history, I don't think it should be surprising to see instances of substandard equipment. The right approach is to face fault head on.
It just seems hard for me to believe it's a quality issue. China today is the top producer of high quality steel. Its metallurgic industry produces far more complex product than gun barrel today, used in a wide range of industry from construction to military, and aerospace.
As far as I'm aware, the VT4 gun barrel is the same as used in the ZTZ-99 series, yet the PLA doesn't seem to suffer from such issues that we know of. Nor does Pakistan seem to have suffered such issue either, which operate both Al Khalid and VT4, both model using the same 125mm gun.
I would also assume national acquisition for such products would go through very rigorous and grueling tests, including firing munition at maximum rate of fire, basically imitating combat conditions.
People are quick to jump to quality issues whenever Chinese equipment are concerned because it plays exactly as the propaganda wants. If you look for instance at the Wikipedia page for the VT4, it'll cite incidents where it was destroyed or failed with dubious sources such as "Global Defence Corps", a literal disinformation website run by an anti-China/Russia/Bangladesh indian dude in Australia, or "Militarnyi", a website run by Ukrainian military enthusiasts with blatant bias. So no, I'd rather not play to the stereotypes.