The advancement of what is possible on the FE has not given ample time for FE developers to scale accordingly. That I believe is because of lack of standardization across the WWW and the reliance on existing libraries like Babel to accommodate this gap. The variation of how code behaves underneath now changes depending on what library you use and that tends to libraries or developers overcompensating for their code to run anywhere. IMO, we need to stop inventing the new, ensure browsers behave the same across 90% of users and then start innovating again. Sure, we might have to do this every few years or so, but the gap would keep increasing and thus have longer periods of stability.