Who do you think cane up with and wrote his domestic policies? That’s literally what lobbyist are for. They have these things drafted up ready to go years in advance (just like the Heritage foundation and SC picks). The only thing that might be last minute is the decision to go with it.
They know exactly what the downstream effects of these programs will be. Regulatory capture is a well attested phenomenon, so I’m skeptical of any claims that all the Byzantine policies that just so happen to favor big business came about haphazardly