Boeing may argue that if the packs and bleeds are in the correct position the aircraft must be pressurising. Not necessarily so, as witness the ill-fated Helios airlines 737 flight where the outflow valve was open for the entire flight. The solution is to re-instate in the after take off checklist the first item as "Air Conditioning and Pressurisation....Check - and then change the checklist policy to have the PNF challenge and the PF to respond rather than a one man band job by the PNF.
The Helios Case however is covered in the preflight checklist: Air Cond & Press.... BLEEDS ON, AUTO, SET. If you reconfigure the pressurisation system after that you have to follow the respective supplementary procedure, those are in my outfit on the back of the (single sheet) checklist. Of course any supplementary procedure has to be thoroughly briefed, the procedures themselve is usually pretty short and easy to do. If you still forget to reconfigure the pressurisation after take off that should be cought during the FL100 check which requires the check of cabin pressurisation.
About the ab-initio pilots, that is a completely different thing and discussed ad nauseum elsewhere. Anyway it is not new since ab initio pilots are the norm for the last 50 years or so with many major airlines as well as the military.