Great, you are still moving. Keep doing those efforts and after your body adjusts, you'll find you can make the same effort, with less HR. Or if you keep it high, you'll be faster than previous.

If you are going to keep working with HR, then setting your zones up based on lactate threshold is a better way, IMO, than using your max HR to set them. Here is a method I liked back when I worried about such stuff..... Joe Friel’s Quick Guide to Setting Zones

Nowadays I just ride. Sometimes fast, sometimes slow. I look at my data and compare to previous rides, but mainly just to see general trends for specific segments of my rides where I usually will go hard at it for a time. Usually a good climb. Long flats are hard to find around me.