Your description about the issue is sketchy, there is nothing wrong with disabled input fields but it it sounds like you are making that an issue while the actual issue would be parsing those fields in the backend.
The whole idea is validate the user inputs - be it disabled fields or normal inputs
I’m not trying to nitpick here, my confusion was genuine. These sorts of statements are hugely misleading even for seasoned folks (“what if I missed something in disabled inputs? why crypto suffers from that?”), and in novice developers it creates magic recipe thinking instead of generic awareness that you never want to execute(user_input).
Validate for functional errors then sanitize for injection issues.
Hope it makes more sense now! Sorry for any confusion from previous comments or post