There's more nuance to that. A 4130 steel frame with oversize top and seat tubes...

There's more nuance to that. A 4130 steel frame with oversize top and seat tubes and thicker walls (0.9/0.7/0.9 mm) typically used on touring bikes is also going to be stiff. A too thin down tube will make the bottom bracket flex too much.

This is a quality modern steel tube set:

https://ciclicorsa.com/shop/columbus-spirit-tube-set/

A frame will retail to at least 4x times as much.

https://ciclicorsa.com/shop/cinelli-nemo-tig-disc-frameset/