We can only hope that eventually, they'll add in DPS increases for using the new active mitigation skills to mitigate damage.
Bringing back Shield Swipe, but only for blocks during Sheltron (Also, maybe change Intervention so you can block for your ally and thus proc this too?) - Likely also, make it require blocking a certain amount of damage to prevent being able to pop Shelly on an AA to get Shield Swipe value.
Increasing the DPS value vs cost ratio for TBN (Either by increasing the EDPS it provides, or reducing its MP cost)
Allowing Heart of Stone to proc some damage increase (Cartridges?) upon mitigating a certain amount of damage.
Allowing Raw Intuition/Nascent Flash to proc some damage increase (Infuriate CDR? IR CDR? Retaliation attack?) upon mitigating a certain amount of damage.
If they follow the similar rules of TBN, where both self and other active mitigation skills can proc the benefit, then that would alleviate the concern of disrupting role neutrality. Since, if it doesn't matter if you Shelly yourself or Intervention the MT to proc your Shield Swipe, then you're not promoting any specific subrole for a DPS increase (Also, making the party CD's be more appealing)
I don't know if it's specifically that, or they just don't like how often defensive options are being used primarily for offensive boosts. Such as using Shelltron to block an AoE that won't do significant damage, just so you can Shield Swipe for more damage. Or popping Thrill of Battle purely to enhance Upheaval.
Which is likely why TBN has been unaffected, since it has always been used for DPS neutrality due to the lack of Grit in the meta. In addition, due to it having a requirement for its boost in the first place, by having to have the shield break, it meant that it could ONLY be used for this boost up to DPS neutrality when it was being used to mitigate significant damage. As opposed to stuff like Shelly/ToB which could let you block a pathetic 1 point of damage or didn't have a requirement at all for them to be DPS increases.
Though, as I say... Hopefully they're just using the current state of their newly designed Tanks as a starting point. Trying to get them within a reasonable level of balance before they start to add in their differences in identity. Such as altering the bog standard Tank Trait to fill in some niches (WAR with fat stacks of HP for example) as well as then further going in and altering some other fairly homogenized skills, like giving unique ways to get DPS boosts from mitigating with their active mitigation skills, more unique features on gap closers, more differentiated burst CD's (No more IR Lite for DRK kthxbai) etc.