In all seriousness, I see the point of looking for a frame that supports larger tires if buying new. There are more options on the market now.
However, if the mission is more along the line of buy used / on a budget or continue using what I have then I'd think long and hard about actual use case vs future proofing because "maybe I'll need it some day."
I want to live somewhere where I need larger tires than the 40's that fit into my OG gravel bike. But the reality is that for where I live and ride 30-35mm strikes a good balance. Once a year when I'm on some unmaintained road in Rothrock SF wishing I had bigger tires ... oh yea, underbiking for a few miles. Or I'm on my MTB.