Earlier quoted context omitted.
One thing I'd recommend is making throwaway email addresses using one the domains they own (I think have around a 100). That way, if a spammer gets its, they won't know your domain, and try spamming other username at the domain.
I don't think that's a good recommendation. Spammers are going to find your domain name and spam it at obvious usernames anyway (eg contact@). Besides what use-case do people have for throwaway addresses? In my experience in most cases the addresses you use aren't throwaway at all. Fastmail does subdomain aliasing and I've been using that for years with my own domain without issues. Every subscription I have has its…
I don't think it's a given that spammers will find your domain, if you only provide your email to real people, and give generated emails to online services.