The fact there's not much else to do in this place, the land purchase must have been dirt-cheap compared to ground-level installations in downtown Paris. So, if they needed to be close to decision centers, that's a very good choice.
Apple certainly does well in investing in R&D and looking towards some amount of pivoting.
However, this quasi-exponential growth in spending reminds me of a pathetic moment at a EU commission meeting I attended, on research and innovation public funds in 2010.
The EU commissioner basically complained that Europe had no Unicorns like the GAFAs, but wanted to be reassuring: this is about to change. We will prevail, because we'll spend more on R&D (through tax money) than all of these do together.
With the implicit assumption that the more you spend, the bigger the returns.