Never has before in three editions.
3/4/5E had totally different approaches to and qualities of DMG. 4E had by far the best-quality DM advice and was definitely the easiest for a "noob DM" to run a fun (for everyone involved) game in (esp. with noob players).
Yet 4E had by far the worst WotC adventures at launch. I mean they were super-trash. Every single fault you can point to in an adventure, those three either all had it, or one of them had it in spades. They were so bad I was finally convinced to go back to writing my own adventures (which turned out to be easy because 4E was so good for that).
Early adventures usually have quite a few problems. Which is a shame, because many curious people will get the game and whatever adventure is available, have a bad time with a bad adventure, and conclude that the game sucks.
The main problem is of course that early adventures are made by people who by definition don't have much experience writing adventures for this game, or this version of the game. Worse, they may be relying on instincts from previous versions that no longer are correct. For example, both Hellknight Hill (part 1 of the first PF2 adventure path) and The Fall of Plaguestone (the first PF2 standalone adventure) are incredibly overtuned. This is likely because in PF1, rampant power inflation and an inherited problem with how challenge rating worked meant that the encounter building guidelines were a joke, so you pretty much had to overtune your encounters compared to what the rules suggested. But balance in PF2 is much tighter and unforgiving, particularly at lower levels, so that's going to lead to a bad time and TPKs.
A related problem is that the early adventures are often written using early drafts of the rules, and often a late rule or design change isn't accounted for in the adventure. For example, in the last D&D Next playtest package, kobolds had AC 11, 2 hp, and a +1 attack bonus dealing d4+1 damage at either melee or range. Their Pack Tactics ability would give them +1 to hit for each ally within 5 ft of the target.
In the Monster Manual, the kobold has AC 12, 5 hp, a +4 attack bonus dealing 1d4+2 damage, and pack attack gives them advantage on their rolls.
Now, the numbers don't translate one-for-one – for example, it seems attack rolls are a bit lower in the D&D Next version (only fighters have a +2 proficiency bonus at level 1, for example). But player AC and hit points seem about the same, so it's clear that the published kobold is a much more dangerous creature than its D&D Next cousin.
Why do I go on about this? Because the first published 5e adventure, Hoard of the Dragon Queen, starts with the PCs fighting a group of
8 effing kobolds. Against a typical 4-person adventuring party, that's two kobolds each, and it's a BIG difference between fighting two kobolds with +2 to hit dealing d4+1 damage, and fighting two kobolds with +4 to hit and advantage and dealing d4+2 damage. Even the hp can make a difference – against a typical d8 damage cantrip, 5 hp gives you a 50% survival chance, but 2 hp only 13%.
Now, I don't know if the designers of Hoard of the Dragon Queen were balancing this fight using D&D Next kobolds, 5e kobolds, or some version that was never released, but it would certainly explain why they start the adventure, which will be many people's first encounter with 5e, with such a potentially lethal battle.