Not just likes. Any post a user from another instances sees from you, is also stored on their instance. But I don't think it's stored indefinitely and it's also not stored in a way you can make use of. So if the server your account is stored on explodes, technically there are still a lot of your posts stored all over the fediverse's servers, but there's no feature that would allow you as the (former) account owner to ask for them or easily collect them.