This can be the case, but if any of the engineers on staff spend a day reading docs it should generally be fixable. A 30mb it should be chunked by the build pro

This can be the case, but if any of the engineers on staff spend a day reading docs it should generally be fixable. A 30mb it should be chunked by the build process in such a way that small updates usually cause cache invalidation for only a few kb worth of files. If the library you use to build your SPA (React, Vue, etc.) is relatively up to date you should also probably not be sending the whole app over the wire at once to anyone. Routes and components can be set to only load when the user actually attempts to access them inside the SPA, reducing egress significantly.