The reverse is true.
I meet quite a lot of low to middle level programmers that stick to what they know because it's "the basics", and hence completely lack in experience in:
1 - Writing elegant modern code
Working with experienced C / Java coders to write proper Python is a challenge. They tend to use twice to many lines, ending up with slower and less readable code. They don't use the additional productivity to produce cheap goodies like generated doc, more unit tests, etc. They over-engineer stuff, but let the user experience down. And don't ask them to setup a server without the help of a sysadmin.
2 - Trading efficiently machine time for coder time
Aka you cost 100 $/h, a bigger server cost the same amount a month. Keep the double nested loop and go code something else.
And please setup code auto reload and preprocessors. Because THAT will save time and money down the road.
3 - Knowing the modern ecosystem and how the stacks fit together
No you don't need share this across threads and set a mutex here, put that in redis.
Don't write that in XML, you have JSON/YAML/TOML for that.
Actually don't write that in a file, you have sqlite.
No, you don't want to JOIN that, you have Arrays and JSON types in PostGres. If you got a lot of those, mongo or elastic search will do.
No you don't write sockets manually, you have http, zeromq, wamp and the likes to do 99% of the jobs.
JSON is too slow ? You have bson, msgpack, protocol buffers...
Yeah, this ORM is slow. But it generates the entire validation system, including HTML forms. And it allows for 12 plugins to share a common API to provide auth, history, permissions, registrations, a REST API, security measures, sanitizing and data validation for free. Plus the server has 32 cores so just go with it.
4 - being able to keep up with user expectations
No I have no idea how to code in assemble. I can tell you however that the search completion you don't want to add here because it's too much work would prevent the user to think your app is from 2004. And I can get decently performance version of it for tomorrow at a cost effective price.
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Bottom line, everybody has limited time and resources and can only learn so many things at once.
Also different industries have different needs. And sometime you want low level programmers, sometime you want high level programmers.
One could hire somebody who has the skills of both, but you probably can't afford him or her. And he/she is probably not interested this mission anyway