"Within the crypto ecosystem, mixers gain relative to both payment processors and ordinary exchanges after disbursement, isolating increased demand for privacy rather than a broad post-aid expansion in crypto activity."
See also the 2nd reaction on the [What-Used-To-Be-Twitter] webpage.
"anyone who follows development finance closely or has worked in the sector knows that the main challenge is getting the funds to reach their destination and avoid getting diverted by corrupt officials"
Even if the money is used completely legitimately it will be exchanged for goods and services thus ending up in someone's pocket. Someone who may want to buy Bitcoin.