I predict it will be reminiscent to the migration to the threadiverse. Every now and then, we have seen Reddit make some stupid decision, and then we subsequently see a wave of new users migrate to Lemmy. Eventually, one day, I expect Reddit will make such a monumentally stupid decision that nearly everybody bails at once.
That is like what I expect Linux growth to look like. A few waves now and then with each major release of Windows, with each major Microsoft data leak, with each pricing restructuring, etc. Then eventually, Microsoft makes a single fatal decision that causes nearly all remaining Windows users to finally give up hope and migrate.