This video that describes some of the issues with VPN marketing in general is so widespread that it has created old-school SEO sites to game it where they hide the actual search term with white font on white background.
While I would suspect wireguard performance is quite a bit better than a similar OpenVPN configuration, I would want to see analysis of specific setups and what resources they actually use on both sides.
I can't agree with that in this context. People have little idea what they are doing and what they should choose and follow various guides of various ages, pushing people who select an older implementation to select newer algorithms than the past defaults risks negative publicity. Selling rather slow service pretty cheap is how you get the volume in virtually any service market, most users making a choice preventing them from using the network bandwidth they were sold is also a bonus for many companies with inadequate peering.
If the VPN was selecting for performance, why wouldn't they select the null algorithm? In wireguard you seem to have no choices, but in normal IPsec you could make all sorts of different choices that have different tradeoffs, but in general: the weaker and more open to attack, the faster and cheaper your offering can be and the more likely one blog entry by the wrong person kills your company.
Not sure why... probably just not very optimized.