Eh there are lots of reasons why the gold standard is dumb and bad, but this one isn't a good one.

19th century business cycle dating is highly imperfect as modern measures of the economy were not available during this time. There have been some attempts to reconcile this, but they are imperfect themselves.

A gold standard constrains policy which probably works well in an environment without a credible central bank and government, but at a significant expense of growth. Much better ways to get the former without sacrificing flexibility and growth.

And while average inflation was lower under it, gold itself was prone to demand/supply dynamics that caused fairly large short-term volatility.