It’s because the current version has nothing wrong with it. If the Lemmy devs should choose to sabotage the Lemmy software, you’d be surprised how easily that happens when it pisses off all the instances and their owners. Instances will simply refuse to upgrade. And like most things, eventually some fork will win the race to become the dominant fork and the current Lemmy devs would be essentially disowned. Different forks also doesn’t necessarily mean API breaking changes, so different forks would have no issue communicating (at least for a while).