Depending on what you’re trying to do, there are ways to create, update and delete records in different bases, effectively linking them, using Integromat.
For example, I run multiple projects with tasks assigned to collaborators. Because you can’t link bases, there is no way for any collaborator to see their tasks across projects in one base. However, I’ve been experimenting with this and it’s possible with Integromat. Take a look at them - they are worth spending some time to figure out if they would work for you.
DISCLAIMER: I’ve been using Airtable for about a month and Integromat for about 2 weeks. I tried Zapier, Automate.io as well but found Integromat to work best for my use case. I’m also not affiliated with Integromat.