The thing is that you should as the developer clearly allow mechanics that you think help the game in some constructive way.I think Frontier made engineering that way to make it a secondary game-play path. So the idea is that people would not invest right away all their time in this activity and rather do exploration/PowerPlay/etc.. and OP ships would be the exception not the norm. The ships would be engineered "as you go".
Similarly the credit fountain seems intentional to me so money issues gets out of the way rapidly.
It turns out it do not work as intended. I don't know why people wants to get rich quickly in Elite, to be honest or have as soon as possible the deadliest ship. Neither should be possible except on the rarest luck struck.
For example, telling you to look for signals for materials is a way to do it and it would take a lot of time to engineer a few modules in a ship (which is fine and maybe intended). This is not a problem. It requires commitment and as you say only the players that commit the most time would achieve this (with this insanely repetitive mechanic). The REAL problem comes when Frontier says... "OK. We agree that this is insane". And their solution is to allow reboot farming of signals and sites and to make a trader that Charges (in material currency) you usurer rates for your hard earned materials! I think that this is a mistake and shows lack of commitment for the Frontier team to the idea that the system is ridiculous and they seem to actively want to penalyze players that use this officially valid methods. The same as the fast tracking mechanics for PP (dont get me started on those horrifying more than 150 clicks.....).