What are the best onchain privacy protocols? 

Railgun is commonly shilled but are there any other good ones?

Building /veil - ZK Privacy Protocol for Base

Anon community for Veil Cash | https://anon.world/communities/veilanon

/fluidkey protects your privacy. Receive and manage funds onchain without publicly linking them to you. fluidkey.com

Quilibrium

fluidkey

Universal access & verification layer for digital identities. Building a privacy-first future

Seismic is building a privacy stack for evm chains so keep an eye on them as well

The one with large enough anonimity set. Find Railgun on Defillama and it will show alternatives. Check the amount of locked assets.