Fungibility and traceability are orthogonal. Equities markets transactions are highly traceable and also highly fungible.

Bitcoin's fungibility is limited by its incredibly slow transaction speed. (This is true of all cryptocurrencies AFAIK -- even the fastest ones that are only capable of 100K TPS at best.)

What makes you think Monero is untraceable?

- https://arxiv.org/pdf/2408.05332

- https://darkwebinformer.com/chainalysis-successful-deanonymi...

-https://www.sciencedirect.com/science/article/pii/S266628172...

The fungibility of Bitcoin is achieved through layer-2 networks, such as Lightning. No, it is not another cryptocurrency, it is just another technological layer. You are still transfering bitcoins.

Trumps "Bitcoin payment" portrayed extensively by the media was done in the Lightning network.