Will filmmaking become cheaper as technology advances?

It can't become any cheaper than it is now because it's already free to become a filmmaker.

All you need is a camera and you have a perfectly good one on any smartphone which they give away free with certain phone packages. Total cost: Nothing, Zilch, Nada

Your question has a single, simple flaw in it: Hollywood is not filmmaking

Hollywood movies do indeed keep increasing but there is no reason. Worse, they increase while production values fall. Since "Found Footage" became popular, every film now looks like it was made by a complete imbecile. They go out of their way to make film look more amateurish than the audience could produce. It would be almost possible to take images that bad on that aforementioned smartphone that you got for nothing.

I started my filmmaking career when I asked the question

"Is the only way to get better quality to spend more money?"

What I discovered was that spending money was no guarantee of getting quality - the two were independent. In fact, you could make high quality movies for very low budgets. This led me to the question

"Just how low a budget do you need to still ensure a high quality product?"

And as the years have progressed, the answer to that question has become lower and lower as technology has progressed until it has got to the grand total of nothing - nothing but your imagination, that is.

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