I understand (From accepted answer What is the difference between HTTP and REST?) that REST is just a set of rules about how to use HTTP
Accepted answer says
No, REST is the way HTTP should be used.
Today we only use a tiny bit of the HTTP protocol's methods – namely GET and POST. The REST way to do it is to use all of the protocol's methods.
For example, REST dictates the usage of DELETE to erase a document (be it a file, state, etc.) behind a URI, whereas, with HTTP, you would misuse a GET or POST query like ...product/?delete_id=22
My question is what is the disadvantage/drawback(technical or design) If I continue to use POST method instead of DELETE/PUT for deleting/updating the resource in Rest ?