How do the jobs and local economic benefit compare between a steel mill, a semiconductor fab, and a datacenter?

Are companies proposing steel mills and semiconductor fabs directly adjacent to existing residential neighborhoods?

Will those developments pay for the required infrastructure expansions, or get special deals to waive those costs in return for building in that community?

Mostly yes. Everyone would also prefer that steel mills semiconductor fabs get built somewhere else, where they personally don't have to deal with any of the externalities.

Those will likely create lots of jobs. Local industry is good.