Tufte would also want visualizations to be meaningful in addition to factual and clear. If a vendor sells you a propriety visualization tool, they are also likely to include propriety visualizations and analytics. For example, in addition to providing a Tufte-satisfying view of requests/second, the company might include a visualization for the made-up propriety metric "un-monetized requests/second", with the company-proven analysis showing why, if un-monetized requests are greater than some % of total requests, that's a problem that needs solving. Oh! and wonder of wonders, the company happens to have just the solution for the problem. At a small additional licensing fee, of course.

It's a bullshit meaningless metric, of course, and wouldn't pass the Tufte test, but the company gets a profit center.