After you already have a great franchise in SoaSE, why the hell do you downgrade yourselves and make this crap?
I don't think there's much of a crossover in audiences either, from real RTS games such as SoaSE to MOBA nonsense. MOBA games in general seemed aimed at people who cannot or will not play more 'traditional' or larger scope RTS games.
At least SoaSE:Rebellion is pretty damned great. It's a shame to lose yet another developer, but these guys will either go bankrupt or continue to make this RTS-lite crap from this point on.