They do use steel inserts in Gen 3.
Funny that some Bren fan club boys were discarding Bren 2 criticism with "battle proven" argument, while most if not all of this criticism came from battle field experience in Ukraine and several videos on this subject were made in English, Ukrainian and Russian. Well, it looks, unlike some fan boys, CZ paid attention to the real battlefield experience.
Let's see what we know so far against existing design flaws:
1) Flimsy plastic stock hinge. Fixed in Gen 3 with aluminum hinge.
2) inconsistency of accuracy (I attribute this to the combination of the way trunnion is attached with pencil barrel profile). Gen 3 has medium profile barrel bringing it close to HB, and it looks like (but I can't be sure 100% from the vid) they changed the way trunnion-receiver-HG are attached together. I really hope they changed this.
3) Steel bolt riding in aluminum receiver got changed in Gen 3 with steel inserts.
4) Flimsy charging handle that can be easily bent - not resolved in Gen 3.
5) Plastic guide for charging handle - unknown status for Gen 3.
6) Magazine overinsertion issue is caused by absence of support for magazine in receiver. Unknown status for Gen 3.
7) Cast metal gas block destruction. They definitely changed gas block, I hope it's milled in Gen 3. In Gen 2 it was mix and match.
8) Bolt too short travel for reliable extraction-feeding sequence, most affected were 7.62 guns with even shorter bolt travel, but even 665 was too short to my knowledge. Not sure if they changed anything. I would have changed.
9) Technically it's not the issue, but rather poor choice of solution to prevent the issue. Overcomplicated carrier design to address the issue of rebound - they changed design again in Gen 3. A bit of stupid way to resolve the issue, but we will see how good it is.
10) they said "breach part is changed", not sure what they were addressing with this.
11) no changes to plastic [lower] receiver and I personally believe it's a bad choice of material for a battle rifle.
There were several more issues but I don't keep the list, that just from top of my head.
P.S. With current laws this gun has no chances for FRT.