If money's all that's needed to build a fab to match TSMC's 5 nm without prior experience then their biggest competitor would be China's SMIC. They have unlimited funding from the Chinese government because an embargo hurts China's electronics industry a lot more than just price gouging. SMIC, a company with unlimited funding to poach TSMC engineers and actual experience with chip fabrication is still 2 gens behind. Apple's not going to do any better.
Apple's breakthrough came years after acquiring PA semi and Intrinsity -- and neither required $10B in annual CAPEX to maintain their lead in chip design.
