What I see is and what I believe people who immigration to Canada under FSW. Once they arrive and start living most of them are not working in their required fields, somebody is driving truck, somebody is waiter, someone working a caregiver etc.. Their education matters only till immigration process and after it nobody cares what you do and really they don't care to do work in their field for which they get immigration.
Well, this for a bit longer discussion.
Language part is clear - without being able to communicate you have a hard time to become part of the new society. So that one I hope is needless to discuss.
Now the age part is more about thinking how much revenue can Canada potentially get from that person (over the years of working and paying taxes). You might argue that this is individual, but since it is impossible to assess it in advance as you have no idea who will apply and how will they end up doing in Canada, you use a mere statistic data. And what they say is that of course on average potential to pay taxes for younger people is higher than for older people. so if somebody over 35 wants to immigrate, he or she needs to have additional skills that will show a potential to get higher paid salary (French for example).
And of course while you want young people you do not want them too young so that you do not have to pay for their education. That is why those that are barely 18 do not have full points for their age.
And the most tricky education. Here a very long term goal is followed.
Canada as most of the industrial country is heading toward the future when lot of thing will be automated or online. So what it needs are people that are capable to properly understand and live in such society. It already has its good deal of Dufuses, so it is not very willing to import more.
Over the time more requirements on education (even if it is practical knowledge like in trades), do force human brain to excersize and adapt. And these days we know that human DNA is not stable but small mutations do happen over the time as we age, so that pressure to increase mental capacity will eventually lead to the next generation of smarter children.
You might claim what about refugees - well funny enough the way the system is setup if force people to think out of the box to arrive here. And yes they are very prompt to deny lot of visa requests. So same thing apply, mostly only the smartest ones are able to work with system.
EE itself is a type of game where you have several options how to beat your opponent and get your spot on "plane" to Canada. You can either be top of the top (Master or PHD that is under 30 and has a very good language knowledge). You can have plenty money (to pay for different consultants to find a way for you to immigrate). Or you can be smart and seek all options and adapt in order to get through (work on your IELTS, learn French, find a PNP program, or marry a Canadian).
Anyway all those conditions do only apply as a must for the main applicant. There is nor requirement or penalty for children and the points penalty for your spouse is rather mild (no penalty for now official work experience, very mild penalty for education and mild penalty for weak language skills).
So in Canada eyes they only try to get like 50% of people with post secondary education (which is not that much).
So coming back to this case. That person will not get through unless something will change. And that something is rarely point system or immigration system (if then it will be more for worse). So it means that his points or efforts needs to lead to that change (he shall either get more points and get a direct ITA or to find a suitable PNP or other way).