It is to be expected, because those guests can bring people out of the woodwork. It appeals to the industry abroad as well. I wouldn't call any FM author episodes lame at all, whether you get those numbers with the former names mentioned or not, it is very fascinating to get to know the person behind the work. Especially for my own asperations in FM building, when they comment on design choises. Or if I'm a fan of the FM, what could have been when they mention cuts.
As well, it is a huge treat to have anything Thief1/2 related come out this many years after the game. I feel like we just keep winning in this regard. I like to remind myself how nuts it is that we keep getting new FMs. If there is also a episode of a podcast to discuss them, and classic FMs, that's like... the maw plumb on top of it all.
That said I know all good things come to an end, just keep doing all thief related things so long as you're still having fun. And btw I like your regulars too, they are good stand-ins for us who also love and approach thief differently.