It's on the top 10 list of things to consider - along with finding real customers. How high is debatable. If your product/service resonates with customers, you could change the name to something more appropriate later. It might be expensive to buy the right domain, but if you've got $ or stock that's worth something, it's totally doable.

Consider the fact that a brand and the company name are two separate things. Think Uber Cab (Uber), Google (Alphabet), Tide (P & G). The domain name can/should be tied to the product - and the brand. The company name itself can be anything really. As a first step to a rename if you really really want to do it, you could file an incorporation document amendment that says "Company AD15asd Corp, d.b.a. NiceBrand"