C hosing a domain name is actually a two-way choice process. First is you have to know the keyword or the company name you want to have as a domain name. Technically that is called a second-level-domain name. And, the other is the TLD you want to choose. That is .com or .net or .io or dot whatever.
Most of the times the dot com second level domain are not available. Either they are too costly, or are developed or are not for sale.
As a domain investor I tweeted about this https://twitter.com/TLDjournal/status/1405224454074945539
I think, the value of other extension for the same second-level domain will increase if the dot is not available or is too costly. So, if you are holding such assets try to know the current status of the dot com domain name.
If it is fully developed and not available – increase the value of your domain name especially those which are regarded best alternatives to dot com such as .io, .co, .net. etc. Knowing is the key and also check about the trademarks. And, be familiar with the general clauses of trademarks. If you are holding a domain which is registered much earlier than the fresh trademark date then it is a plus for the domain holder.