I’ll cut to the chase. Dreamhost, one of WordPress’ recommended hosting companies (and my personal favorite so far) wrote a great blog on how to change domains and not destroy your SEO. https://www.dreamhost.com/blog/domain-change-seo/
If you don’t need to change your domain, DON’T! You’ll notice they say that you will REDUCE the amount of damage done. You’ll still probably have a dip in traffic. If you can bear that in the short term and if in the long run it’s better to change domains, go for it. If not, just don’t change your domain.
If you change your domain name, follow their advice. Make sure you forward all necessary URLS and pages. Make sure you update all your social media links to your site and then notify Google through Google Search Console.
If you don’t use Google Search Console… I don’t even know what to say apart from “you should get it!” It’s by far one of the most valuable SEO tools you’ll ever have. I use it almost exclusively.