I think GP’s point was more about the truth for the consumer of the site. As a user, I trust a site to deliver the content it intends to deliver. Of course this is just a trust by proxy with Cloudflare because you’re trusting the site’s judgment on who to trust. As a user of the site, it makes me just a little bit more uncomfortable knowing there’s another layer of indirect control over the content coming in.
Of course this is all just philosophical anyway. We’ve not even touched on external module usage.
That is what Cloudflare is doing. Using a Cloudflare security product intends on modifying the website it's proxying. Everyone involved in running the website - the original website owners and Cloudflare, intends for this to happen.
The one exception is Cloudflare turning this on by default for free 'customers', but hey, if you're not paying really what leg do you have to stand on?
Of course this is all just philosophical anyway. We’ve not even touched on external module usage.