@BJL
I don't follow the tech side the way you and Bernard do, but there was little doubt in my mind when both Nikon and Canon entered the 'MILC' market, Canon had a different strategy to Nikon. Canon knew, or at least guessed correctly that the tech/demand wasn't yet ready to supersede their pro-grade 1Dxx DSLR's. They had a huge installed base of users heavily invested in their EF glass so they went lenses first, body second. The 'R' wasn't to compete with the Z7 or the high end Sony's but rather an affordable prosumer category box that most pros would easily add as a backup to their main cams, serve as a taster for new tech and attract a large number of their existing amateur installed base - though I'm confident that the last one fell well short of their hopes.
Development of the EF glass was at an end; the RF mount was the future. They said so, clearly. Their introductory lens choices, IMO, echoed that. There were no (apart fm a 35mm) run-of-the-mill lenses. Two exceptional f/1.2 s and zooms, one an 28-70, f/2 - glass designed to excel, pique the interest, burn a distinct hole in one's wallet but above all to serve notice that Canon were entering a new paradigm.
From a totally biased personal perspective, today, I'm looking at the lenses, their IQ and the build quality - the 85/1.2L in particular. Roger Cicala's (LensRentals) teardown and reviews tell me that the RF 's are good, very good. What's left is the body to mount them on - and so far we've had the first of an expected total of four new bodies due this year ('announcement', I doubt delivery).
I'd hoped for a 1D quality pro-build. From the teaser I see, what I'm guessing, is a new-generation 5D series. I doubt I'll be spending upwards of $10,000 on glass to mount on a prosumer body, other than as a backup.
IMO, the race is still wide open. Sony have market share, good bodies, a clever pricing strategy in that their older models are rolled over, reduced in price and serve as an encouragement to 'follow the line'. The issue with Sony is that despite universal praise as to the IQ of their lenses, I just don't like them. So much so, that the only native lenses I use are two Batis - an 85 and a 40 , [plus a Zeiss/Sony 55 ZA f/1.8]. On the plus side, Sigma et al will be manufacturing ART grade E-mount glass in the future.
Nikon are out of the starting gate, no more, no less. Canon likewise, but this year will be telling - I'm expecting stellar lenses in both IQ and build. If they can produce a pro-grade EOS-Rx to mount them on, that may be enough to encourage me to switch.
As it stands, my interest is piqued, but thoughts of a Leica SL2 continue to plague me.
Canon has typically been one to announce new products only soon before release, which is the strategy of a dominant player: earlier announcements largely undermine sales of the company's own existing products. This mixture of a development announcement with just a few highlight specs — along with talk of "many lenses coming soon", is instead in the style of a less dominant or even trailing player; one that want to persuade potential customers to wait a while longer, rather than buying into a competing system now (or in the cynical worst case, "jumping ship").