Aznvasions recently released a video covering a shadow buff to Ash's Bladestorm - the tl;dr is that it now acts as a proper pseudo-exalted, where lots of melee mods affect it. While there has been a Savage Silence Bladestorm build knocking around for a good while, this is an overall buff where you can access higher damage with less effort: https://www.youtube.com/watch?v=dRSejZ0zniQ
I of course wanted to test this on Zariman Thrax since I'm stocked up on Mod Boosters and love trying new things. The result was simply slapping the Thrax with a wet noodle, as recorded here: https://www.youtube.com/watch?v=S5z2pnWUZFM
You can see how the Grineer are easily one-shot when Silence isn't active, but it has no noticeable effect on the Thrax and takes forever to chew through their Overguard. Once Silence is active, it does some damage, but not a lot. If it's so slow at base SP levels, it will only get worse at higher levels as their Overguard increases. Therefore, not really a viable option
Even though there are no Banes for Thrax, and Overguard isn't affected by Viral's damage boost, the damage disparity was wild enough that I went into the Simulacrum to try and see what's up. The result is that Thrax seem to have an innate resistance to finishers/finisher damage: https://www.youtube.com/watch?v=RheS5nPKg4s
You can see that without Silence active, Bladestorm performs its animation fine on the Grineer Eximus and takes a chunk out of their Overguard. Meanwhile the on-hit clone damage does absolutely no noticeable damage to the Thrax's Overguard. Once Silence is active, Bladestorm one-shots the Grineer Eximus, and it does some damage to the Thrax's Overguard, but still not a lot
This remains true even when the Thrax's Overguard is gone: https://www.youtube.com/watch?v=wsbFGBlafvg
No damage without Silence, pitiful damage with Silence
tl;dr: Bladestorm is a fantastic trash killer, but still not effective against Thrax or Demolishers