Transmeta’s CPU was not performance competitive and thus had no path to success.
And as for Apple itself, they had built the first iPhone on top of ARM to begin with (partially because Intel didn’t see a market). So they were already familiar with ARM before they even started building ARM CPUs. But also the developer ecosystem familiarity is only partially relevant - even in compat mode the M1 ran faster than equivalent contemporary Intel chips. So the familiarity was only needed to unlock the full potential (most of which was done by Apple porting 1p software). But even if they had never switched on ARM support in the M1 the JIT technique (compiled with a better CPU and better unified memory architecture) would still have been fast enough to slightly outcompete Intel chips on performance and battery life - native software just made it 0 competition.