This is a deep misunderstanding of when “the issue” arises. That same multiplier tells you how much faster than realtime a block can sync even if using a BDN. It has very intentionally been targetted to this range, and use of a BDN cannot make lower multipliers acceptable. Projects like Turbogeth which change the multiplier independently of the gas limit are the only way to make higher gas limits practical to sync on commodity hardware in reasonable time periods, and even they have clear technical limits.