Just catching up and saw this, which I wanted to agree with and amplify on this. I can't be bothered doing a year-by-year comparison, but if you were to run one, I suspect you'd find at the most around ten seasons in the last 100 years since they first participated in league football in 1920/1 where their average attendance was higher than ours.
A less exact exercise, but one much quicker to carry out, is to look at how often a club has finished outside the 15 best-supported clubs in the country in terms of a season's average gates. Our figure is twice since 1895. Leeds, in their much shorter history, have a total of 41 (and their forerunner club, Leeds City, had a further ten, managing never to attain this feat after their election to the Football League). FWIW, Wolves, another club supposedly giving it large about their support relative to ours last in a recent game, total 70.
Like you, I hate all this "my club is bigger/better supported than yours" stuff that you see a lot on social media now,but I've generally thought it prevalent among idiots on social media. I'm quite happy to acknowledge Leeds and Wolves as clubs with fine support bases and illustrious histories. But when they start chants at our stadium that question us in either area, they're really not on very firm ground.