That’s a good question, and it’s something I always consider before buying over-ear headphones.
I haven’t seen official replacement ear cushions for this model yet, but hopefully Nothing will make them available. Ear pads are usually the first part to wear out, even if the headphones themselves are still in great condition.
If official replacements aren’t released, there’s a good chance third-party options will appear once the headset has been on the market for a while. As long as the mounting mechanism isn’t proprietary, replacement pads from brands like Wicked Cushions or similar manufacturers often become available.
It would definitely be great if Nothing sold ear cushions and other wear-and-tear parts separately. It’s better for users and much more sustainable than replacing an otherwise perfectly working headset just because the pads have worn out.