DNS is not centralized. You can enter whatever DNS server you want. The problem with plain text DNS is that in countries like Turkey over half million domains are blocked in DNS level. Even if you enter your custom DNS, Turkish ISPs MITM the queries and respond with are IP adrress that says that the domain is blocked. DoH prevents such attacks. For this reason once again huge thanks to Mozilla who fights against opressing regimes.
DNS is not centralized. You can enter whatever DNS server you want. The problem with plain text DNS is that in countries like Turkey over half million domains are blocked in DNS level. Even if you enter your custom DNS, Turkish ISPs MITM the queries and respond with are IP adrress that says that the domain is blocked. DoH prevents such attacks. For this reason once again huge thanks to Mozilla who fights against opressing regimes.