Yes, it’s true that one should not develop software which is too crippled but don’t forget that premature optimization is the root of all evil… One does not generally know how his/her software will be used in the future.

However, I don’t think this applies to all projects and software. There would be cases where software is just meant for a lot of people. Also, what if the software turns out to be so succesful that people outside the original social group want to use it? It would be nice if you wouldn’t be required to start over from scratch, because there is no way your software will scale.
Also, if the future consists of software programs that are only being used by one social group. A lot of those groups will probably be getting very similar software. It seems to me that it would be a lot better if they were all using a product that is a little more standard, because this would probably be beneficial to the communication between those groups (or software programs).
And if leaving out a ‘feature’ like scalability in order to reduce development costs is beneficial, why not also leave out things like documentation and clarity? This would reduce costs even further at the cost of reducing the product lifespan.

Maybe I just missed the point of the article, but while I think it is a good idea to develop software with a certain group of users in mind, you should code in such a way that the program can be expanded.