You can't make Bitcoin anonymous because its blockchain is transparent. You can achieve varying degrees of privacy which almost always come with certain tradeoffs.
Mixers are custodial and closed source. You have to trust them not to steal your money or keep logs. Without having access to their source code it is difficult to verify how effective their mixing algorithms really are.
Coinjoins can be
expensive and users often make basic mistakes like merging all their mixed outputs together, combining private coins with toxic change, or spending to a reused address which links them to their previous history.
Swapping to Monero in the most private and decentralized manner can be cumbersome and is not usually suitable for large amounts due to insufficient liquidity.
Other options like statechains, Lightning and sidechains have not gained much traction but they can be useful tools.
Using Bitcoin privately is difficult without it being the default on layer 1. Ongoing improvements will continue to be made. You should explore various options and decide which solution is most ideal for your needs.