I think it was Stephen Hawking who observed that the opposite of knowledge is not ignorance, but the illusion of knowledge.
In the case of marketing, thinking you know your consumer, while in fact they are someone very different, is more dangerous than not knowing them at all.
Observe your customers, the language they use, their initial facial expressions, body language, what they say and don’t say etc.
Get closer to your customers. So close that you can tell them what they need well before they realise it themselves.
Ps: With COVID-19 and social distancing rules, there are other tools that can be used to get closer to customers.