What is most common and secure is to only allow access to the webserver using TLS 1.2 or 1.3. This will naturally prevent older insecure browsers to access your website.
When allowing TLS 1.2, pay attention to its configuration, because some cipher-suites or parameters are not very secure. TLS 1.3 has the advantage to be fine without any particular configuration. Only allowing TLS 1.3 is more secure, but you might find it too restrictive.
When allowing insecure configurations (and thus older browsers), you might (or not, depending on the exact configuration) endanger users with newer browsers that would be fine otherwise. Indeed, an attacker might be able to force its target to use an old and insecure TLS configuration. This attack would be impossible if all TLS configurations allowed by the server are secure.