If that one site you cite (Hey I’m a poet!) grinds them to dust that’s best. (Melting them works to!)
You’d be amazed what’s recoverable ! Maybe not all but something if something is beter then nothing ! It’s about how much time & money you want to put into it.
They just run a grinder along each platter. Enough to make recovery extremely difficult.
Another place had a shredder that you could toss whole phone books and even electronic components into. They would toss drives into it and what came out was no bigger than maybe 2-3”. But that was a heavy duty machine that I’m sure cost lots of $.