I don't 'want' anyone to change their deck to something they don't want to play. 'Should' is not a command. I'm completely indifferent to what any given player wants to play. It's not like I'm snatching the deck out of a child's hands and forcing him to play a different deck. I'm providing feedback and assume that as adults we can filter advice, taking what we like and what we dislike about a set of suggestions and go from there. If you don't want to play metal, that's fine.
I didn't see any comment related to OP not wanting to run metal, only that his idea for a Silvally memory focused deck centered around a Volkner engine. I don't think that's a particularly effective way to run Silvally, speaking from my experiences messing around with Silvally variants. Silvally is very much a card that needs secondary attackers, much of its utility lies in being a colorless accelerator of energy which, along with its ability is why it has seen use with a lot of high cost bulky basic attackers in the past such as Lapras and Celesteela. There really aren't good lightning partners that take advantage of Silvally's acceleration because lightning types hit nothing relevant for weakness these days, (even if they did, there's a lightning memory) and share a weakness with Silvally. If what he's doing is working for him, he can feel free to play it to his heart's content, if not, well, that's what advice threads are for.
I didn't see any comment related to OP not wanting to run metal, only that his idea for a Silvally memory focused deck centered around a Volkner engine. I don't think that's a particularly effective way to run Silvally, speaking from my experiences messing around with Silvally variants. Silvally is very much a card that needs secondary attackers, much of its utility lies in being a colorless accelerator of energy which, along with its ability is why it has seen use with a lot of high cost bulky basic attackers in the past such as Lapras and Celesteela. There really aren't good lightning partners that take advantage of Silvally's acceleration because lightning types hit nothing relevant for weakness these days, (even if they did, there's a lightning memory) and share a weakness with Silvally. If what he's doing is working for him, he can feel free to play it to his heart's content, if not, well, that's what advice threads are for.