Bitcoin can't talk for itself unless someone introduces it to another one. So I don't believe on saying products talks by itself since one need to know what is the product is and it needs someone to introduce it to them, may it be the store or the advertisements created for it. The same things happen to Bitcoin. No one will know Bitcoin if no one is introducing it or showing it. After all Bitcoin is just a code and does not talk human language.
@OP promotion, campaign, marketing, and advertisement are needed for something to propagate especially when the target is citizens all over the world and Bitcoin is not exempted on that.
One of the brands employed a unique strategy to reduce advertising costs for its smartphone products. Xiaomi, for instance, has opted to eliminate traditional advertisements altogether. This drastic measure has significantly cut down their advertising budget. However, what's intriguing is how Xiaomi has managed to imprint in the minds of everyone that when it comes to finding a feature-rich smartphone with official warranty, the answer is Xiaomi. Its reputation has spread through word-of-mouth recommendations from satisfied customers.
Bitcoin follows a similar pathit can promote itself if its existence brings tremendous benefits. However, considering Bitcoin's current position, achieving global recognition is undoubtedly challenging. Some countries still do not accept Bitcoin as a viable form of currency. As more and more people adopt the mindset that Bitcoin is the easiest investment without KYC (Know Your Customer), it gains prominence. When the Google search trends for such keywords start soaring, the result is an automatic surge in Bitcoin's value.