What he is suggesting is that he can contribute 10%. Everything he contributes up to 4% is matched by his company (ie a 4% pay increase). Usually its a little more complicated than that. Like they'll match 1:1 the first 2% and then 1:2 the next 2% for a total of 3% matching funds.
In Norway there are no matches. The company just have to pay 2-7% of your salary to your fund each year. For tech jobs it's mostly at the top of the range.
The companies do not have to do this. It is purely optional, though there is a tax advantage I believe. Most "professionals" have the option at their company.
A bigger problem is that the 401k offerings are fairly bad usually. The people picking them are HR staffers who frequently don't have experience in finance, so the plans frequently have murderously high expense ratios. Even to the point where some companies repackage Vanguard funds that you can get on the open market for 10x less.
total employee and employer contributions (including forfeitures) - the lesser of 100% of an employee’s compensation or $54,000 for 2017 ($53,000 for 2015 and 2016 not including "catch-up" elective deferrals of $6,000 in 2015 - 2017 for employees age 50 or older) (IRC section 415(c))
So the max is basically 200% match of the individual's contribution, which is maxed out at $18,000 for an individual under 50.
Many companies are doing odd things now with half percentage matching. So they will say they match all of the first 4% and then the half of the next 2%.