I'd argue the opposite myself. Maybe weapon speed allowed for such a tactic that wasn't an issue with TB mode but in that case rules of engagement for the videogame adaptation ought to be revised, instead of reverting to an even more literal translation of the system into a new medium. The way I see it, the TT system as is doesn't work in a CRPG so I'd look how to tweak and adapt it so as to provide an experience that better uses the medium it's in from a systems, narrative and mimetic degree whilst also evoking the feel or idea of the source material at the same time. In this sense I think Pillars does a very good job at polishing and improving the IE systems and at evoking some of the D&D feel, but could also do more to make combat even more flexible so as to open to more roleplay or strategy options within it and so on.
It's a contrivance or artifice, I agree, but I do think it's less jarring with the diegesis than TB is because it's much easier to abstract the "pause" plane from the "real" plane as it's a literal pause in action or time, where all characters interact with one another simultaneously, opposite to seeing every character acting individually at a time whilst everyone else stands in place in what seems like a continuous, linear timeline. It also doesn't help from a narrative perspective to see what should allegedly be a battle, i.e. a moment that normally should be frantic and chaotic, be chopped up to fine bits of individual actions in what seems like a vacuum of idleness - yes, you would be chopping up a sequence using the pause button in RTwP, but I do think that a lot of the chaotic or frantic effect remains in seeing all characters act simultaneously and so on. To make a comparison, if you pause a battle sequence in a film, the image will be a still one but in the frame you'll still see a dynamism or tension that even in that still image captures a sense of chaos or disarray. I do think immersion, feel and storytelling is affected differently in both cases, though again I also feel pacing is the biggest concern for me.