I believe the issue is less that advertisers are unwilling to buy display web ads; it's more that they no longer place a premium value on buying them from brand

I believe the issue is less that advertisers are unwilling to buy display web ads; it's more that they no longer place a premium value on buying them from branded publishers when they can reach the same users on many different websites with programmatic buying. This hugely devalues quality publishers and increases the value of lower-investment publishers who successfully create a lot of pageviews. The latter inventory used to sell for bottom-of-the-barrel prices, but advertisers have decided it's pretty similar in value to reaching the same user on a high-quality site. The best offensive weapon quality websites have against this trend is native advertising: create high-quality sponsorship offerings that commodity display ad impressions can't directly compete with.