That, and Drew Karpyshyn is long gone, too...
I'll withhold judgement until we actually have a better idea of what this new Mass Effect actually is. Others have done well enough working on second-hand IP: Fallout is a great example, and Halo 4 looks to be doing just fine without Bungie's involvement, etc. There are probably still enough of the original team at Bioware even if the three biggest names are gone.
...on the other hand, Mass Effect is a huge tentpole for me personally, as my favourite franchise of this generation. I'd rather see it end now than be subjected to a "new trilogy" situation where I have to start actively decanonizing stuff in my mind. I don't want to be that guy