You will note that I said "most", not "all", " new and improved". But for most recreational divers (not do extreme depths, deco, or DPVs) a well tuned reg will breathe great.... Whether it's a 70's Conshelf, brand new Aqualung legend elite, SP 109, or brand new A700 (or whatever their current claimed best is). This has nothing to do with the pace of other industries changes, and more to do with the fact that a regulator is just a demand valve... And physics doesn't change. Incremental improvements have been made, but they are mostly of a nature that the average diver won't notice any difference (other than the weight of their wallet).
Respectfully,
James