Canon is positioning themselves to win the marketshare game. $1,500 EOS RP will sell well as they have the branding, installed market/users, and have undercut Sony on price. Yes we all know that the a7III is a better camera, but the value proposition is huge for current Canon shooters who want a cheaper entry point to mirrorless cameras that will work more cohesively with existing glass.
It's a bit awkward for Canon to release the EOS RP alongisde a bunch of $2k+ L lenses, but they're simultaneously signaling the future-state of the RF mount for professional use even if the first iteration of the EOS R cameras are not up to to the caliber of Sony's best offerings.
They're doing enough to stop the bleedover to Sony, and maintain their dominance on the camera market in a post DSLR world IMO.. They're basically telling Canon users "wait for us...we got this"
I've been shooting Sony for 7 years now and its been a pretty awkward experience because there were times that Sony seemed to be wandering around in the dark and didnt understand their customers well. It took awhile for them to get a lot of things right....Contrast this to Canon who, as late as they are, seem to know what products to bring to market right out of the gate.
To be clear, I'd never switch from Sony because I really believe they lead the industry in all the areas that matter to me, and you can see how badly they want to win and as Sony customers, we benefit from that....moreso now that Canon is playing to win now too. This is more the marketing/sales/strategy nerd speaking out loud, but market share and sales has no bearing on how I feel about my camera and lenses. 
It was right before a storm so the sky was at its most interesting. 
