Voting with my wallet

[Felessan]

The point of leveling other classes to level cap is you help both the economy through gathering and crafting lower level items while leveling it (DoL/DoH) which benefits other players who did not cheat their way to level cap. Leveling a new class helps new players by also having someone to play with and do lower level dungeons and such when in the sense of DoW/DoM classes instead of lacking in people to play with or help along the way for those who didn't buy their max level characters.

The price tag is too restrictive to make a difference on a large scale, thus the real impact for low level activities will be around zero. Actually I see that most people who'll use it comes from the crowd that already gave several other classes at 50 level, and this people usually have means just to skip everything you mentioned and go for "optimized" levelling route.
I don't see it included now as game is still expanding, but at something like 5-6th anniversary, when playerbase is already stabilized - they'll probably add it.

WoW has had a steady decrease in subscribers for a long time but the exodus was only hastened with P2W options such as buying level skip to 90. If SE added such an option to FF14 I would quit too, if they keep it pure vanity only items such as pets, mounts and such then I am fine with it. WoW is not an example that should be followed these days unless you to wish to do more damage than good upon this MMO, it is still hemorrhaging players at a very high rate. Do not repeat the same mistakes WoW made.

WoW decline for most part have nothing to do with decisions that were made, it's just way too old already. MMO tends to have a major decline from its peak number on their 10th anniversary and there is not much to do to battle this. Games become old and people just get tired with the same game for many years.
Most "successfull" MMO peaks out at their 5-6th year, be it WoW or Everquest/UO/FF11, and than gradually start declining.