Renault should have stepped up this year, but the engine looks even slower and has worse reliability (even in a Torro Rosso the moment it was really pushed it blew up). They are way behind and I honestly do not see how they will be able to bridge the gap without massive investment in just the PU. And with these regs, it is now too late to pump 200 million extra in this PU. So basically Renault is F'd and so are their customers. Nobody can be happy with that. RBR have no choice but to get out of these contracts if there is no improvement soon.
And why Renault think they would be better off with their own team? They could not even get their engine to run without outside help last year. Now it is even worse.
Audi? I doubt they want to get in at this stage. Maybe after 2020. They do not need a Honda kind of PR disaster.
Frankly, after yesterday's race, why would any manufacturer want to step into this poor excuse of a racing series?