Regarding carbon allotropes such as graphene: could an alien civilization have developed from pure organic technology with metals being relatively unimportant?

So let's hypothesize an alien civilization. They sit pretty much where humanity did 20,000 years ago in terms of intelligence and technology, and their planetary conditions are largely the same. Meaning, they will have just as easy a time working with fire and metals as we did.

However, there's a caveat. They have access to a fungus that naturally creates all of the carbon allotropes in an easy-to-use form. The fungus is even highly electric in a way that makes the application obvious (i.e. jolt of electricity, and the fungus moves briefly), giving said civilization access to electrical circuits millennia before we did.

Would it be plausible that such a civilization would skip the metallurgy stage of technological development and focus more on carbon-based allotropes? Maybe they pick up metallurgy as an important but not day-to-day relevant sidecraft for what carbon can't do -- much like how our modern civilization treats ceramics. But make no mistake: their electronics, their infrastructure, their homes... carbon-based, baby.

...I'm a huge fan of the slimy biotech aesthetics you see in late-80s to mid-90s anime. And I'm just wondering how plausible it is to meet aliens that look that cool.