There is nano which doesn't have any fees at all if you are going into that, but personally I would recommend some chain like polygon or stellar etc. with low fees and to use stablecoins like USDC on top of it, personally, the fees are so negligible, and if they are still an impact, maybe pay them on nano but polygon's fees are in cents iirc, there are other low cost stable coin based tokens too i guess.
For whistleblowing though, Monero would be top tier.
Also I am pretty sure that there are already systems which can give a list of numerous crypto accounts from one thing but still monero would be my best choice for such kind of things tbh given how usdc can still hold/censor your money in a somewhat degree y'know, maybe there are some freedom usd things or something but at that point, having them in monero makes more sense.
These are the few applications of cryptocurrency which can genuinely be used (I am a bit of crypto skeptic because I don't like what the community has become, my only respect is for monero community really and some nano contributors or some chain developers in general but they form a very small portion and the markets don't move because of them and no matter how much trust I have in a project, I don't trust markets and I don't want to play a fool's game compared to stock markets where there is genuine productivity in conservative stock markets generally speaking although that productivity is also de-linking thanks to AI in S&P 500 )
To be really honest, I just don't like crypto personally except stablecoins and that too in just a very small degree, That is my personal experience that I am not going to take part in something which feels like an speculative asset no matter its use-cases as most of these would just converge on one or two and if not, they would have some niche use cases and their use case right now is feeling more and more like a ponzi scheme more and monero is the only one which doesn't feel that way really.