>>214743115
I'm not sure what this is but fascist scum o algo.

>>214743497
Sorry I didn't answer your question yesterday, I read it but then I forgot to answer and when you reminded me again I couldn't post.
Personally, I don't think there's anything magical about back extensions that would bulletproof your back, they are just a hip hinge variation not too different to a deadlift or a good morning, the difference is that the exercise is set in such a way that it's much harder to load, the main muscles moving the weight are the glutes and hamstrings and the lower back works isometrically.
Look at pic related and mentally rotate the guy 45º degrees, the movement is exactly the same as a deadlift or good morning.
If they feel good to you they are a fine exercise to do, but don't expect them to be too different to a deadlift.
I think the reason some people love them is because unlike a deadlift they aren't loaded as heavy so people instinctively think they are better for your lower back because it actually doesn't have to work as hard.