Well, I was responding to your comparisons between the methods. You listed distinct methods used by OD&D/1e, 2e/3e, and 4e. You then said that 5e has "the issue" (problems with encounter-building guidelines in a game with "adventuring-day" resources) because it does...none of those three methods.
Well, the classic D&D method has been extinct in mainstream play for about 40 years now.
4e doesn't have the issue.
So that leaves either the 2nd ed AD&D approach - which is to have rules and procedures that in a formal sense are pretty hard to get right (in terms of encounter balance) and that the GM is expected to work around via fudging; or else the 5e approach, which is to use guidelines that are sufficiently "down-tuned" that even a non-technical group of players who have already spent a fair bit of their resources for the "day" will be likely to succeed at the typical combat encounter.
Personally I think the 5e approach is superior to the 2nd ed approach, although neither actually appeals to me.
It provides guidelines that are lenient to the point of being not very useful
I think they are useful - they mean that a GM who follows them is not likely to accidentally TPK their group. And for non-technical, non-wargame-y players - which I think is a lot of the current player base - the "lenience"/"down-tuning" won't adversely affect the play experience.
One of my theses about 5e, for quite some time now, has been that its designers effectively tried to abdicate many actual design decisions in the first place. Not all, of course, as that would be impossible. But certainly a lot of them. That was why the 5.0 DMG was so full of advice that boiled down to, "You can do X, or you can not do X. You're the DM, you decide!" without even a gesture at explaining how, or why, or when--or giving worse-than-useless "advice" about it.
I think 5e is a pretty tightly-designed game.
On the PC build side its maths draws heavily on 4e D&D, with many correlative departures from tradition (eg fighters get their 2nd attack at the same time magic-users get 3rd level spells, ie 5th level - although tradition for a second attack is 7th level in AD&D (fighters go from 1/1 to 3/2) and 6th level in 3E; and fireball etc do a fixed number of dice of damage rather than a level-scaling amount) yet the player-facing aspects of PC build are close enough to tradition that it causes little outrage.
On the action resolution side, it has a stat/skill system that is deployable in something like the 2nd ed AD&D way (ie more-or-less as a descriptor system that the GM establishes some fiction around, calling for rolls if they like), in something like the 3E way (ie using "objective" DCs for task-oriented resolution) and that is not wildly different from 4e in the actual skill list itself. And its combat system is a cleaned-up version of 3E and 4e.
And on the GM side, it supports the mainstream approach of low-stakes, frequently free-form exploration leading from combat encounter to combat encounter - there is nothing too toothy to get in the way of that, like a skill challenge framework or other out-of-combat conflict resolution - and (as we're discussing in this thread) the combat encounter guidelines mean that accidentally TPKing a group is pretty unlikely, even though resource management is largely on the traditional per-day model.
Now none of the above is very appealing to me, but that's not because of bad design. It's because of deliberate design away from my preferred approaches to D&D and to RPGing more generally.