I'm not quite sure what you mean, or at least how that follows from my post. Can you elaborate?
When classes are designed to emulative of past editions, you also have to design the system to be as well, including all of, or at least some equivalent of, the measures taken that insured balance.
You see some of that in 5e. Concentration, the ostensible squishyness of casters vs the ostensible bulk of martials, etc, but these aren't collectively a great execution.
Put another way, 5e tries to be a lot like older DND but without any of the systems that made older DND work better, or at least work closer to what was intended.
Casters that had the power level 5e casters do used to have to slog through ages of leveling with a character that could be killed by a stiff breeze. Thats a far cry from 5es design where casters can very often compete with, or even exceed, what Martials can do.
And meanwhile Martials are, if anything, slightly stronger than they used to be, but have comparitively little going for them due to the devaluing of many systems (exploration, downtime) and the shoddy execution of others (skill system), and thats before you get into to the class design themselves, as much of this topic was concerned with.
Put even more concisely, 5e as designed was too concerned with emulating its predecessors and not concerned enough with being a functional game.
And that tracks, as its well-known at this point that this was a deliberate design choice to apologize for 4es existence.