Well no, I don't concede that, because I know that polls like this have zero predictive value.
But let's say I do. The point, whatever one thinks of the predictive value of polls, is that the Brexit Party is a problem for the Conservatives, and leavers more generally, and not for remainers: they'll split the Tory/leave vote without picking up seats themselves.
The other point, if you do believe these things can tell the future, is that even if remainers fail to vote tactically, and vote Lib Dem even when that will let the Tories in, they are still going to take seats from the Tories.
In other words, remainers have nothing to fear from a GE (unless they do something stupid like implement a government of national unity): whatever happens to Labour, it's very likely to result in a majority for a second referendum (which - reminder - we currently do not have!)
On the other hand some remain parties do have rather a lot to fear from a GE: the Lib Dems, if it becomes impossible to frame Labour as leavers-in-disguise; and CHUK or whatever they're calling themselves right now, who are polling at 0%. They are definitely turkeys being asked to vote for Christmas, but I don't see what choice they have: remain is all they've got, and it's going to become more and more obvious that Corbyn's plan is the only path to remain. Ditto the Tory rebels. If they're seen as blocking it their post-parliamentary career goes up in smoke too: they'd become symbols of stupid, slippery, self-interested hypocrisy.