Twitter is in quite a vulnerable position as a company.
There hasn't been much in the way of user growth. There hasn't been much improvement in technology or features.
The stock price hasn't really gone anywhere since the IPO 7 years ago. Which limits stock incentives for executives and employees.
I presume that talented executives and engineers wouldn't find a career at Twitter appealing. The kinds of people that might be passionate about Twitter in its current form might not be the kind of employees that make Twitter better.
Twitter is really vulnerable for some kind of replacement.