> adopting an established valid opinion to guide the team's development

Different requirements allow for different settings. Coming from an Enterprise Application background, I found this being more often the case or the only case. Working with different teams, developer fluctuation, different time zones, different skill sets, a framework guides the development process far better. Vanilla JS is something that should be avoided in team setups. There is too much mental overload that is usually not justified by the benefits. It is like deliberately choosing assembler language when Java or C# would do the job better. Frameworks got a bad rep. For me, they are tools that should be used.