What do you mean by "locks your account"? If you're using Photos on a Mac then everything is stored locally. If you're using iCloud, you still have the option to download all the originals locally. The only people that would really make use of this are those that don't know how to open the Photos library to access the photos directly.
Probably not from their online service, but unless you switch on “optimise local storage”, all of the files are already on your local disk in JPEG or HEIC.
I make a lot of photos and videos, those take up a lot of space. 128GB to store everything locally won't cut it. That's why I have a backup in form of Dropbox.
Additionaly, I plan to amend that with a self-hosted solution. I know, this reeks of tin foil, sure. However, whenever I read a horror story of someone getting locked out of their accounts and loosing access to their data a chill runs down my spine. Everytime I see captach start popping up too often I wonder if I'm suddenly, for some reason getting close to getting banned. This is the same reason why I have a GSuite account under my domain and never use login with Blabla solutions.
Curious, what happens if Apple locks your account (not in their ecosystem but M1 got me apple-curious ;)? Can you still export you're data, photos?