Looks like normal end of season appearance combined with just a touch of cercospora leaf spot. Generally not a big deal and cleaning up and disposing of all this season's foliage should help a lot.

Overhead watering is usually the culprit (it promotes leaf spot fungal infections) so try not to get the leaves wet for long periods of time. Using soaker hoses or drip irrigation may help. Using the sprinkler or hand watering around sunrise may also help. This looks like the foliage of a macrophylla/serrata. If so, the ends of the stems already have flower buds. When removing the dormant blooms and leaves (throw them in the trash), cut the petiole string that connects the leaf to the stem and not the stem. The Spring 2021 flower buds are inside the stems, at the ends of the stems and are not visible until they open in Spring and resemble tiny broccoli heads.

Thanks for the comments! I use drip irrigation so I don’t think that’s the problem. I’ll trim the plants this weekend. Thanks for the help! Much appreciated :)

I also use drip irrigation because a few of the hydrangeas suffered from this problem when I bought the house. The drip and sanitation practices has helped minimize the spread to other hydrangeas newly planted nearby. The plant can also get the fungus at the plant nursery, at the wholesaler and at our homes as this fungal infection is easily transmitted and is almost everywhere; too much humidity (environmental or from over-watering) might also trigger it... There are now very low priced fungicides that help control this and minimize the severity of the outbreaks if applied early (they become visible from July onwards but the fungicides have to be applied before that). With only one plant, I would try keeping the leaves & air humidity as dry as practical, use new mulch and follow clean sanitation practices.