It already exists without crypto tokens and it's called a referendum.

Different countries use it to different extents. The Swiss Country does a lot of it, for example.

But referendums are not always a good idea and are extremely prone to manipulation by the media and populism (see Brexit). Minorities are also underrepresented in referendums, which poses a real problem with these things.

Having an elected government with separation of power is definitely always better, than whatever DAOs are doing.