I've noticed the same. Companies are disguising what are obviously marketing, advertising, or promotional content as "transactional." Experian is probably the most famous of these offenders. They send "transactional" emails every month that can't be opted out of when they notice changes in my credit file (everyone's credit file changes every month almost by definition!) It's scummy, intentional, and IMO breaking the law.
> They send "transactional" emails every month that can't be opted out of when they notice changes in my credit file
And you can't even try to unsubscribe without creating an account. And, if I don't _have_ an account, it is (pretty much by definition) NOT transactional.