While what you are saying is of course true I think that is not the point he makes. I fly both of the Boeing types and a lot of FOs I fly with especially on the 787 say similar. Obviously we all take time to adjust to something new but the quality of some new hires on Boeing is well below the required standard especially given the weight of responsibility the OMA places on Captains with the narrow constraints put on FOs.
Short and rushed training courses coupled with the fact there is no requirement for wide body time do not help either.
Bottom line on this issue(and its a big issue the company ignores) is that talented FOs have left and will most certainly leave in the future due to a ridiculous lack of advancement opportunities. Currently they won't even give a guy his 3rd stripe when he earns it.
Training have been telling management for a while that soon DECs will be "unrosterable" under blue line restrictions. This is due to a lack of SFOs to as said above to "babysit".