Victorian design is usually described as excessive, which is accurate and explains nothing. The cause was industrial: mechanised production made ornament cheap for the first time in history. Carving that had required a craftsman could be pressed, cast or printed in quantity, and a rising middle class bought decoration precisely because it had recently been the preserve of people who could pay for hands.
So density is the point rather than a failure of restraint. Every surface is worked because an unworked surface signalled that you could not afford otherwise. The colour followed the same logic: synthetic aniline dyes arrived in 1856, and the deep purples, greens and oxbloods that had been ruinously expensive became available, then immediately fashionable.
Wood engraving gave the period its graphic voice, capable of extraordinary tonal detail on the same press as the type. That is why Victorian layouts stack many typefaces in one lockup: the wood type catalogue was the palette, and using more of it demonstrated the printer's stock. Modernism spent the following century arguing against all of it, which is the clearest evidence of how total it was.