[hombre_fatal]

I don't think your comment follows from the evidence presented by the author.

For example, the blog didn't even beat out the result above it which is "older content". For all we know, the blog was the last relevant candidate for that search query, the author doesn't demonstrate otherwise.

The only spammy thing we can tell from TFA is that the blog post's publish-date is set in 2019 when it was clearly published in 2016. But we don't know if Google knows that and is already penalizing them. Nor if it's an effective attack.

Also, the author doesn't demonstrate that the modified-date is inaccurate or spammy. CMS software will update this if you go back and correct a typo, or somehow mass-transform a bunch of blog posts. For instance, I once had a dead-link-finder plugin on Wordpress that gave me a UI to patch urls in old blog posts that would have updated the modified-date on all affected posts.

I don't see anything in TFA that suggests that the blog was benefiting from spammy behavior.