I've seen some cases (in stories, on the internet) where people call each other '老鸽'. As the literal meaning 'old pigeon' doesn't make much sense, I think it's slang but I haven't been able to find out the meaning.
So what exactly does '老鸽' mean?
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It will make a lot of sense if you see this word in some video channel comments to mention the holder (Youtuber or uploader on other websites).
“老” or "老是" by itself means "often".
As is also mentioned in other answers “鸽” is short for the slang "放鸽子" (release a pigeon) which means one can not keep his promise. Now a days it is a very popular word to describe situations that a channel holder promised to upload some video soon but postponed for a long time. Or a uploader started a weekly series, but skipped some weeks, or just stopped updating that series.
"老哥" means "big brother" or simply "Bro". It has almost exactly the same usage and emotion as "Bro". You can use it to call any male.
To sum up, "老鸽" is a pun. First it means "老哥" and can be used to call a male fellow, mostly a uploader, but in a joking way. It also means "老鸽", short for “老是放鸽子”, which means "usually cannot keep the promise". It is joking that the uploader is known for often postponing the schedule.
It has other versions like "鸽鸽" which is a pun for "哥哥" and "放鸽子" and "鸽王" which is a pun for "歌王"（king of singers） and "放鸽子之王" (king of procrastination)
A part time individual game video channel holder posted a message saying "Because of the isolation during the pandemic, the video that was scheduled for the next week is postponed." This is funny for the channel followers because usually isolation will give him more time at home so that he can have more time to make videos. It is too obvious that he is just trying to find whatever excuse for his procrastination. So a channel follower comment that:
"我来给这位 老鸽 翻译一下：咕咕咕咕咕咕咕，咕咕咕，咕咕咕。"
“let me do some translation for this habitual postponer, [mimicking the sound of a pigeon]”
Well, it is not meant to be any offensive. It is just funny.