How to move and remove specific years of iCloud Photos to reduce storage?

You're aware of all the Photos features you'll lose doing this? Photos keeps track of people in all those photos, locations, dates and times, other things found in the images, etc. Photos is a heck of a lot more than just someplace to store pictures. A lot of relevant data about those pictures could be stripped and lost forever if it's just dumped into basic folders.

I caution this because I know people who thought Photos was just an annoying way to store their pictures and didn't grasp all that it does under the hood. I can instantly find past photos I took at a trade show in Los Angeles by going to Map and zooming in on the convention center. All pictures I ever took at that location show up. I can find what I'm looking for instantly, without a clue as to which month or even year it was.

I have 20 years of digital photos outside of Photos and they may as well get deleted. I couldn't find a particular picture of someone, "on some trip" if my life depended on it. I'm considering going the other direction: loading it all INTO Photos and adding some GPS and other data as I'm able.