Don’t worry friend, as far as I am concerned from all the publicly available interviews so far, they have that in mind too. Check this part from windowscentral;
There are not yet definitive specs for PC requirements, but Age of Empires IV is being developed with inclusivity in mind. A new engine that doesn’t rely heavily on a single processor core will immediately make an enormous difference. Even those with beefy PC hardware can sometimes see Age of Empires II: Definitive Edition chug along because of the old engine. The ultimate goal is to create a game that can be played the same on a relatively low-end laptop or a high-end gaming rig.