While small businesses may work on a year to year planning, or at most 2 or 3 years. Most institution and corroboration will always have something call a "strategic" plan for at least 5 years. The place I'm working at both have a short term 5-years strategic plan, and a long term 10-years strategic plan. If you have paid intention to companies like Google, Facebook, Apple, Intel .etc. you will regular hear them talking about their "strategic" plan, and they will be all ways on the order of 6 or more years. In another word, what Yoshi said is completely "normal" in the actual working world once you get above certain size.
Of course, having a plan that far doesn't mean it's rigid, that's why you have the term "robust planning". For example, I just finished a meeting today where we evaluated where we are in our 3rd years of the current 5 years plan. We also reviewed where we are currently at in respect of our 10 years goal. With the COVID hit, we admit it will be difficult to reach all the goals we set for the 10 years, but we still acknowledge that the direction we want to move toward to, it's just the matter of adjust expectation and changing the method of getting there.
And simply put, a large company with large staffs need that kind of planing to keep the workflow coherent and "focus". I don't know how you interpret Yoshi's word, but it's not like he meant SE is start putting money in the bank to make the game last another 10 years no matter what. It simply mean he and his team has an "idea" of where they want to take the story and the game into the future, maybe how it will pan out and end. That means his staff know that whatever work they're doing in 7.0, 8.0 will be not just about those expansion, but also about laying foundation and lead to a certain conclusion in 10.0. That's how you can develop a "coherent" story over time. An example is G'ahara Tia, a character who was seal away in the original game and brought back as the central character nine years later.
Again, samething about real life workplace, the strategic plan is to let the staffs know that whatever they're working on and accomplish this year is also a milestone toward the long term goal, it means their works have a focus. Which is something absolutely important in larger organizations.
And lastly, if you still want to by cynical about his words, then there is actually a physical proof for you: SE just upgrade all the data centers hardware this years, that's NOT the kind of investment you would make if you already plan an exit in the near future. That doesn't mean SE will keep the light on even if everything goes wrong in the future, but right now, both their word and action does indicate they have a long term commitment in FF14.