The thing you have to ask, though, is are those more affordable third party options for Sony E-mount really any better than using comparably priced EF lenses on Canon R cameras? As far as functionality goes, they're not really "adapted' lenses. Every EF lens works just as well on an RF camera as it does on an EF camera. SOmetime better (in terms of AF accuracy).
I understand your point, and I'm sure different people will see it differently. However,
for me, yes, I believe those more affordable third party options for Sony E-mount would be better than using comparably priced EF lenses on Canon R cameras, at least so far as the lenses themselves go.
For example, the Sigma 85/1.4 DN is smaller and lighter than any comparable Canon EF options (signfiicant to me), as well as cheaper. (That said, the Canon system does have the Samyang RF 85/1.4 AF, which from the reports I've seen is actually quite a good lens, and it is a similar size and weight to the Sigma.)
The Tamron 70-180/2.8 is more than 30% cheaper than an EF 70-200/2.8L IS III, and is much smaller and lighter (again, significant to me). It is also not much more than half the price of the RF 70-100/2.8L IS.
The Sony 55/1.8 has pretty good IQ, from everything I've seen, yet is relatively small and light. I cannot think of a similar lens for the Canon system, once portability is factored in.
The Sigma 24-70/2.8 DN seems comparable to the Canon EF 24-70/2.8 II in many ways, but is comfortably more than 30% cheaper (at least where I am).
So, I could have a lens kit for Sony E-mount which is smaller, lighter and cheaper than a broadly comparable lens kit I could have for Canon R cameras even using EF lenses and an adapter. And the prices for the R5 and R6 are making the Sony bodies seem much better value thean I've ever thought before too
YMMV.
I think that right now, Sony's system is the most advanced in terms of the number of lenses taking advantage of what mirrorless can offer in relation to lens design, partly because it's the full-frame mirrorless system which has been around longest, and partly because there are third parties like Sigma and Tamron making lenses for it. Canon is taking advantage of what mirrorless can offer for lens design too, of course, but Canon's approach has been to focus on high end, but large, heavy and expensive, lenses. Yes, there are a few smaller, lighter and relatively cheaper options, but there aren't many and to be honest I'm not that impressed by them (at least for their price). Nikon's approach has been to create a set of high end f/1.8 primes which are fairly small and light and high quality, albeit they may be seen as on the expensive side given they are "only" f/1.8. I don't necessarily mind Nikon's approach, but of course some will much prefer Canon's approach. Anyway, presumably there is a good chance that the three systems will become more similar than different over time. Will be interesting to see where Canon's system is in a couple of years.