Mail in a box (Miab) suggests [0] some good TLD and some bad TLD. This is not to bash on Miab. But to understand from where these suggestion comes from. I own some names with cx, ninja, run and some others. Why would be bad to have a custom domain email address that doesn't belong to the good list of Miab (or any other domain...)?
I was planning to make some personal (and work) email addresses with those cheap domains and fastmail (or some other hosting), but now I'm not sure about it.
Any particular reason?
[0] https://mailinabox.email/guide.html
I do have a global block list based on certain gTLDs.
The list isn't one chosen at random based on the long list of gTLDs out there, but based on real time feedback from my honeypots, and my customer feedback reports, so SPAM getting through the other filtering techniques in use, usually with zero false positives on them.
Many of the gTLDs that are abused the most are ones that had fire sales in the past to get them off the ground.
As mentioned in other replies, .xyz is a SPAMers wasteland. That one would cause the most difficulty getting through anything.
The others that made my block list are probably not ones you would guess.
So, I wouldn't be too worried about things in general. None of the large providers do blocking on gTLD. Only a few smaller ones do. If the domain was sold for $1 getting-off-the-ground, it could have been picked up by the SPAMers cheaply for quick turnaround and abuse.
Simply avoid gTLDs, they might close with little notice and are known to increase prices drastically. The OG gTLDs (com/net/org) and ccTLDs are the safest bet.