Using of ERA in combined ops is still debatable. In the era of information war, its the one who knows first, sees first, and fires first. Then comes the technicalities of training for one shot one kill, running the tank and maintaining it.
A UAV per troop or per squadron should be considered for surveillance and spotting targets. Its input should go into BMS to allow commanders to make real time decisions without waiting for orders from rear HQs.
I would argue that the usage of ERA has never been and never will be a debate, especially in urban warfare. it is simply a no-brainer. Infantry needs to train around ERA, not the other way around, it is that essential to a tanks survival.
Though I do agree with the second part, in any engagement, regardless of wether it involves armor (but especially so when it does), the victor will mostly be the one that spots, engages and hits first.
Even a stock T72 can easily knock out a VT4 if it spots and shoots first, but with modern optics, sensors and Recon that possibility is reduced or negated. Where ERA has most often shown it’s usefulness is in Ambushes and against Infantry, since ERA was in fact originally designed against HE and HEAT projectiles, APFSDS protection came later, and modern ERA protects against Tandem charges too, apart from an APS, it is the best counter to a modern ATGM systems. It is cheaper and lighter than making the base armor thicker and can be readily replaced.
Just due to the way ERA works, having it on the roof of the tank where the armor is generally not that thick, can save it from a top attack ATGM, since it will effectively negate most of its penetration (in the case of HE/HEAT charges, including Tandem charges).
Coming to UAVs and BMS systems, the honest truth is that BMS systems are generally underused, especially in tanks.
While The BMS system in the VT4 particularly is fully capable of working alongside modern UAVs, receiving live feeds and so on (this is also possible in the older BMS systems in AK and AZ, but it’s not easy enough to do to where it would be beneficial many times), I doubt it sees much major use outside basic battle planning. This is not just a reality in the PA but in most armed forces, even the BMS systems in the Abrams and Leo’s are (or at least were historically) scarcely used to their full potential, reason being that these systems aren’t generally designed the best. Unless they are outsourced to someone who knows how to make a good, usable, ergonomic interface and also give it enough processing power to not just be a hassle during combat to operate.
Think of older infotainment systems in cars, they can be so annoying, Archaic and slow that sometimes they negate their intended usefulness and despite logic saying that the military would have better/cutting edge systems, such is not always the case, especially because the military doesn’t really upgrade these systems often compared to how rapidly UAV and software technology is progressing.
In the PA BMS systems are relegated to Command tanks, and for effective use of these systems (because they can definitely be very effective), I would think that the command tank would need to be passive instead of proactive, getting data from multiple sources and communicating it to the rest of the squadron effectively, trying to ensure its own survival to maximize its benefit, while also being cognizant of the fact that for the commander to effectively use the BMS, he will need to often divert attention to it and to communication instead of doing his usual job of spotting for his gunner (which in the AK and VT4, the commander can generally do a better job of spotting than the gunner due to independent sights).