I currently have 3 older steel road bikes.
1984/5 Spectrum, 6 speed downtube Dura Ace.
1996ish Voodoo gravel bike rebuilt as a 1x10 with a bar end shifter.
2001 Tallerico with 10 speed Campy Chorus ergo shifters.
All downright amazing bikes. I would say Ergo>bar end>downtube.
For every metric I can think of. I'd race my Tallerico tomorrow, no concerns. I do race the voodoo, I'll upgrade eventually for weight and wheelbase. The shifting is good enough.
I wouldn't enter the overweight citizens race on the Spectrum, I'd die. I love it but progress has marched forward.
I don't hate downtube shifters at all. I don't hate steering wheel stick shifts either. They are classics now, fun for loads of reasons. Not performance.