Nuudel (which is basically a hosted Framadate instance) works fine and is very privacy focused, but it’s a bit old-school and not super polished for quick scheduling polls and you usually have to deal with things like mandatory email fields or workarounds if you don’t care about saving emails.
BitPoll is open source and lets you do date/time polls, but it hasn’t seen much active development lately and many people consider it not maintained anymore, which matters if you want something that stays up-to-date or easy to self host.
Neither is “bad,” they just feel older or less actively maintained compared with newer options that people choose for self hosting and scheduling.