That sums things up nicely. Thargoids have been "the optional menace" since inception and by design.Precisely. No stakes, no consequences, no threat.
TBH thargoids could have been the perfect tool to downsize the bubble, and maybe rethink the hyperspace travel to reshape exploration and pathfinding gameplay. They could (and should) have been both terrifying and game shaping.
They are just an other disjointed ride in the park.