OLD SCHOOL, I'm not up to date as much as I should be regarding the making of SPECTRE, but I am almost positive that no part of it was made in Hollywood.
But, as you say, it costs a hell of a lot of money to make a movie in LA LA Land ..... so most major productions are made elsewhere where advantageous tax deductions are being offered.
Major film productions are now and have been underway in Canada and down south where these tax advantages are offered in an effort to find work for within their jurisdiction.
But one of the major disadvantages is the fact that you must use the residents of that location that offers the tax advantage. This does not apply to the principal actors and major production individuals but it does cause a problem for the SAG members residing within California and several others states and locations.
I am also not up to date regarding the details of making movie production more affordable in Hollywood, but it does require a lot of attention.
I often wonder if Arnold attempted to remedy this problem while he was Governor? That is another thing I have no idea of.