I think that's too simplistic. First, you can have more than one vector. More than one model even. The limitations here are cost, performance, memory and bandwidth. Second, search is of course subjective to some extent but that doesn't mean there's no right and wrong at all. A lot of that stuff boils down to context and having enough data in your context to come up with a good query.
And of course getting systematic about evaluating your search ranking performance. A lot of companies don't do that at all. A product manager checking things manually isn't quite good enough here. If you are just winging it like that, vector search isn't magically going to make it better.
And of course a text field is not a great source of any amount of meaning unless the user types a lot. Especially on mobile phones where typing is both tedious and error prone this is actually a huge problem. And the solution isn't better keyboards or training users to type better/more. If your users have to type a full sentence on a mobile phone before you return results, you've already failed them hard.
But what can you show them after they've typed merely two letters? Mostly vector search is more effective in recommendations or more like this style querying. Textual searches tend to be all over the place. The shorter the queries, the less useful vector search becomes. What's the meaning of "ba"? There isn't any other than that it's the beginning of something that may or may not start with those letters or have some of those letters in them and maybe even in that order.
The classic view of search is a text field and a list of a results is not the best mental model for this. Mostly Social Networks, Google (and others) try to pre-empt you having to search for anything by just magically showing you what you didn't know you were looking for. And when you search for stuff, they show you that other stuff anyway. Using Tik Tok is basically using search without using a text field. It just feeds on your behavior. Your behavior is all it needs to know as a context. It's not wrong as long as you keep on looking at stuff. The more you use it, the smarter it gets.