Yes silver obviously plays a massive part in the game, but again, just because You or I choose to fish in a certain way or choose to spend our silver or gold on better/best gear, doesn't mean everyone is going to fish that way or spend their silver/gold that way, its just personal choice by the player, same as the 2 ponds part of your reply, what You or I may find fun and the best pond, may not be what other people find fun and the best pond, again personal player choice.
Yes, bigger setups, Game and IRL produce bigger fish, but again, this isn't guaranteed, like I said previously, there are many many factors that may be a reason for not catching a double figure fish, just because you have been there a lot doesn't mean you are entitled or you should expect to catch a 10kg fish, you may never catch one or you may catch one on your next cast, you might get someone turn up once and catch a beast, or someone fishing there constantly and not catch any, it's just the way it goes.
I have fished at Bear for ages and for some unknown reason I never catch a Carp that is over 15kg, despite using what you would think would catch a fish that size pretty regular, is it frustrating?, yup. Do I deserve to catch bigger fish because I have spent ages there with the right setup, No. I just take what the lake/pond/river gives me and cast again.