These are great things to do if you want to buld a community around a project (which does help keep it going). But it's also OK to just build what you want and publish that and then maybe accept contributions under whatever terms you feel like. Community management really is an entirely different skillset from software developement and I wouldn't want anyone to be discouraged from open sourcing their software if they…
However, the landscape has shifted. When an Open Source project becomes successful today, creators often transition the original product into a proprietary version with added features and support, available only through paid access. This practice undermines the original Open Source project, and usually end off killing the original project.