It doesn't make much sense to me -- how changing the language could possibly affect EVM code on the net?
Existing (deployed) contracts will still work the same regardless if Solidity changes.
A comment from a reviewer of the article:
Once a Smart Contract is compiled and deployed it is irrelevant what happens in future versions of the Solidity language.
Another reviewer was concerned that Solidity source code could behave differently depending on the version of the Solidity compiler used. The concern is valid and addressed by Solidity introducing a version pragma:
Source files have to specify the compiler version they are compatible with using e.g. pragma solidity ^0.4.0; or pragma solidity >=0.4.0 <0.4.8;