The first question.
WHAT A FRAMEWORK PROVIDES
Components, as a way of structuring interfaces Automatic updating when data changes Routing between views Conventions and tooling
WHAT IT COSTS
A build step A learning curve Code downloaded, parsed and executed by every visitor Dependence on an ecosystem that changes Ongoing maintenance
WHEN IT IS WARRANTED
Substantial application interfaces Complex state changing frequently Many interactive views sharing data
WHEN IT IS NOT
Content sites Marketing pages Anything a content management system already handles Pages with modest interactivity
WHAT THAT MEANS
A large proportion of sites built with a framework did not need one.
WHAT TO ASK
What problem does this solve that plain markup, styling and scripting cannot?
WHAT TO CONSIDER INSTEAD FOR CONTENT
A static site generator, or a content platform.
WHAT TO CONSIDER FOR MODEST INTERACTIVITY
Plain scripting, or a small library.
WHAT TO WEIGH MOST
Who maintains it afterwards.