I don't think it's deceptive to have an MIT-licensed core editor (which is distributed by MS under a custom license) and proprietary extensions.
Like many OSS enthusiasts, I did some initial research on VSCode/VSCodium and decided to install the latter (similar to Chrome/Chromium).
As I kept using it I discovered that some MS extensions would refuse to run on VSCodium without workarounds.
At that point I was fully aware of the license situation and still decided to switch to VSCode for convenience.
My point is that most software developers are capable of understanding how VSCode and its "useful extensions" are licensed; it's not a new concept. And from there, each individual can choose what tools they use according to their preferences.
Like many OSS enthusiasts, I did some initial research on VSCode/VSCodium and decided to install the latter (similar to Chrome/Chromium). As I kept using it I discovered that some MS extensions would refuse to run on VSCodium without workarounds. At that point I was fully aware of the license situation and still decided to switch to VSCode for convenience.
My point is that most software developers are capable of understanding how VSCode and its "useful extensions" are licensed; it's not a new concept. And from there, each individual can choose what tools they use according to their preferences.