Not all domains are equals when it comes to email deliverability. One important factor taken into account by spam filters and Email Service Providers is the domain age.
It shows how long your domain has existed.
How does domain age impacts my deliverability?
As a rule of thumb, the older is your domain, the better will be your deliverability.
Indeed, most ESP will consider that brand new domain are less trustworthy than aged ones.
Domain that has been created less than 3 months ago are more likely to have deliverability issues than older ones.
Yet, having an old and well established domain doesn't mean that your deliverability will be high.
It's only one factor among others. And it is important to always keep in mind that an healthy email activity is the best way to keep a high email deliverability.