Just guessing he meant "Modern test equipment is built not to be repaired" BY THE END USER. The module is replaced by a Factory Authorized Servicer. No Service Manuals, No Schematics, No Component Level information. No modules for sale either, at least for the customers...
But that would be incorrect as well. Every big brand sells you individual parts, boards, modules, you name it. You can usually also get service/maintenance manuals, too (although often without schematics, but for replacing modules that's not really an issue), either for free or paid.
Some big brands (i.e. LeCroy) also accept you sending in a board for repair, which can be noticably cheaper than sending in the whole instrument.
Unless you are under warranty, you'll be paying for "Authorized" servicing only.
Not really. I lost count of the newer out-of-warranty test equipment I have repaired over the years, and had little problems getting spares and documentation for it.
As I said before, the way repairs are done has changed, but in general modern big brand kit is still repairable.