The product being open source doesn't prevent the situation the OP mentions. It just provides a mitigation or a workaround by forking.
I also hope it won't happen but many good projects have gone this way before.
In this case the investment is not for the password manager but for a new identity service. However if that doesn't end up providing the promised results, the shareholders will start looking at the existing successful product to extract more value. After all they own part of that now and they want their returns. It's just what they do. This will clash with the users' best interests sooner rather than later.
Then it becomes forking time but can they find a good maintainer? Open source is not always a guarantee for continuity.
Of course if the new project pans out this won't happen but it's a gamble, and one the existing userbase never asked for.
I also hope it won't happen but many good projects have gone this way before.
In this case the investment is not for the password manager but for a new identity service. However if that doesn't end up providing the promised results, the shareholders will start looking at the existing successful product to extract more value. After all they own part of that now and they want their returns. It's just what they do. This will clash with the users' best interests sooner rather than later.
Then it becomes forking time but can they find a good maintainer? Open source is not always a guarantee for continuity.
Of course if the new project pans out this won't happen but it's a gamble, and one the existing userbase never asked for.