And this is the second, more problematic issue: timely fixes. A lot of design flaws and issues needed to be dealt with at the time and were left, and with each passing year became more of an entrenched problem compounded by new features.
Whats annoying is a lot of things were fine as they were and were made worse. The classic (engineering) is one such example where the unique modules pre engineers pretty much did what was needed (small, specific boosts and tradeoffs) rather than the heavily grindy, centralised feature we have today.
Powerplay is another: if FD had doubled down on fixing it like they have with EDO, it would not be the clusterfudge it is now to fix.