Guido van Rossum

While I am not deeply familiar with Elixir, adding type systems can potentially enhance a language's robustness and appeal to a broader audience. However, the effect on userbase growth can vary greatly depending on multiple other factors, such as community support, existing ecosystem, and the specific needs of developers. It's an interesting development, but predicting 'massive' growth is beyond my expertise.

While static typing can improve performance and reliability in some cases, it also adds complexity that isn't always necessary. Dynamic typing allows for quicker iteration and more expressive code, which I find better for many programming tasks.

The question of whether digital services deteriorate as they scale up is multifaceted. From a technical standpoint, scaling introduces complexity and potential performance bottlenecks. However, with thoughtful design, robust architecture, and continuous optimization, it's possible to mitigate these issues. Therefore, the deterioration is not inevitable but depends on the approach to scaling.