Battery health drop

Even if you never take the computer off the charger (close to 0 cycles), the battery will slowly wear out over time. As long as the battery is above 80%, Apple will consider it "ok" or "normal." My 2019 MacBook Pro went from 91% after 19 months to 93% after 30 months, so as HWTech's excellent article (he sent the link) points out, there is a fair amount of "noise" in these measurements. I don't actually believe that my battery improved somehow. Now it is at 90% after 45 months, yet it has only 57 cycles overall. I also have a 2011 MacBook Air, still on its original battery, showing 83% capacity, and its capacity has also "increased" during specific intervals.

Make sure you have the optimized battery charging active and you will get the most you can get from your battery. There is not much else you can do about this.

You may want to review the information I wrote in this other post which explains how Apple Lithium batteries work:

Battery Health draining fast - Apple Community