Scaling got us here and it wasn't obvious that it would produce the results we have now, so who's to say sentience won't emerge from scaling another few orders of magnitude?

Of course there will always be research to squeeze more out of the compute, improving efficiency and perhaps make breakthroughs.

Another few orders of magnitude? Like 100-1000x more than we're already doing? Got a few extra suns we can tap for energy? And a nanobot army to build various power plants? There's no way to do 1000x of what we're already doing any time soon.