With a wider definition of “marketing”, it could make a bit of sense:
If you take as “marketing” everything that helps your target audience find you and the things relevant to them inside your offers, then, yes, Cardano as a whole could use a bit of marketing: Great landing pages for projects, developers, end users, guiding them to good, complete, and definitive documentation how Cardano works and how they can achieve their goals with it.
You could count that as “content marketing”, but I’m really unsure if that really helps. I would love if more “content marketers” would prioritise correctness and helpfulness over stupid impact KPIs, but the real-world experience is different: they prefer shilling and overpromising over information. So, I’d be much more inclined to just include enough funds for documentation/education into everything else and let the experts rather than the marketers do it.
Once you have that content, you can maybe, just maybe, do a bit of SEO, search marketing, maybe even influencers.
I don’t see anything of that even remotely reflected in the current “growth and marketing budget”, which is why I will not vote for that and will want to send them back to the drawing board: https://forum.cardano.org/t/cardano-growth-and-marketing-budget-proposal/143055/21