The only Bureaucrat on our wiki refuses to talk to or help anymore on their suggestions or requests. It's so bad that he devoted his time to finding memes to explain why he can't help, rather than using that time to help.
Unless it is really an issue, I would just let it go for now. That being said, you could have a community discussion about who else should be a bureaucrat. Once there is concensus, ask the current bureaucrat to promote that user. If they absolutely refuse to, then you can try asking staff (with a link to the community discussion). However, unless the current bureaucrat is actually harming the wiki, staff are not likely to do anything.