FWIW I still think it'll be Corbyn's decision whether he leads the party in 2020 though it definitely looks like Boris is out of the picture (for the time being). To be honest, as big an issue as that is the fact that there's a very decent chance there will no longer be an election in 2020! The whole thing has gone somewhat awry but I'm not sure I'd go so far as to call it obsolete (or realistic!).