Bitcoin is a very strong brand, and if this moment disappear, it would be a big blow to the whole crypto world.
But if he slowly retire, many new quality coins will replace him there will be no big problems.
In any case, bitcoin was sentenced to fall due to a break in his community.
And because of that, it will be difficult to have a high-quality fork on bitcoin in the near future, and problems such as high fee and slow transactions make it currently almost unusable