I believe that that is already done to some extent. The streaming is separated out from the user input handling/search and background analysis.
However, it also has to be said that the experience of slow search under some conditions is not universal and some people (like myself) with moderate server platforms do not suffer many of the problems that others do (I can’t speak to all use cases - because there are some that would be far to intrusive to my system for me to attempt to replicate - but, for those examples that I have been able to replicate, the performance on my system has been entirely acceptable). As a consequence, I think it is fair to say that there is probably a lot more to these issues than simply suggesting that more cores should be utilised to accelerate processing.