Final Fantasy is not a brand based on uniformed consistency in product improvement and evolution. Therefore, it's a brand name alone and nothing more. After FFIX, each mainline FF began to differ widely in battle system from the next. If you took away the FF brand, FFX, FFXI, FFXII, FFXIII, FFXIV, and FFXV, could each be seen as games from a totally separate series. The main thing that links them is the brand name of Final Fantasy. If each mainline FF was running concurrently in a separate sub-series, there could still be uniformity to the brand, just like how a car or phone manufacturer has different models evolving concurrently, with each getting new model updates. FF doesn't do that. Instead, each consecutive mainline FF is so different from the former that it makes the brand only a name and nothing more. This is not Monster Hunter or Pokemon, where each mainline instalment builds off the previous entry while adding new features and improvements. People have realised this, which is why some mainline FF games could get skipped or ignored if other games in the series look more interesting.
You know, in economics, they say that any rational choice is made based on a weighing of cost and benefit; the choice with the highest benefit being the one picked. You might not share this belief, for whatever reason, but humour me for a bit. Say it's a brand name alone and nothing more. So what does Square Enix stand to benefit from sticking with it? Linking themes of crystals, including Cid, chocobos, airships, the prelude and more in almost every iteration is tough, especially when your story and design has to fit within those boundaries. What is the point in SE limiting themselves within these seemingly trivial bits of Final Fantasy if the name is without the means to induce a purchase? A brand is not just a name, it's a relationship between the buyer and seller. At its core, this is its function.
I already explained in the second and third paragraph why the unique characteristics of each FF become secondary consideration for the consumer. There aren't enough high-budget RPGs going around to begin with nowadays. Each FF is released with large time gaps in between. A lot of JRPGs nowadays are low in quality, leaving there to be even less substitutes for the specific cultural experience in higher quality. Simply put, the lack of quality RPGs out-prioritises the choice of withholding purchase of a main title Final Fantasy game for a future one. What do consumers stand to benefit when they withhold a measly $60 purchase in return for 3-5 more years of waiting? If the marketing was done well and if they're convinced on the quality, then people are going to buy it because it's a numbered Final Fantasy, a name and trait attributed to quality titles.
Of course, what I say may not be right just as what you say may not be right, but if my understanding of theory is anything to go by, there is no reasonable way to conclude that each main FF would significantly detriment each other's sales, the time frame between each title being the most logical reason I can give you among the other few. You can't say that XII will significantly hurt X's sales, and the simple reason why is because XII will not be marketed nor sold alongside X. By the time XII should've gone into full marketing mode, X's sales would have already become negligible. Some cases are different, such as FFXIII: LR against FFX/X-2 HD. These titles released within the same time frame so people likely substituted one for the other based on preferences and their current available income.
Just so you know, I am
not saying that people won't substitute FFVII Remake for FFXV. That will definitely happen; it's the nature of the world. But you don't make a gross generalisation by example of a friend not buying XII for XIII. The real question when it comes to substitution is and always is, to what degree? In the end, there is no data to support the extent in which the VII remake would hurt XV or otherwise. You don't know whether this substitution effect will outperform the benefits from bolstering the brand with the VII remake, plain and simple.
If you're saying that the brand name means nothing, that is an opinion, which I'd argue to be unrealistic as far as understanding how businesses and their marketing work. If we cannot share an understanding on at least this fact, then I'm afraid any further arguments would just end up being fruitless.
I understand that you do not want the topic to derail any further. If you have anything to say, send me a PM.
