Ona slightly related topics how colourful our our waredrobes?
The thread's poll is far too long for me to vote in, but this is a question I'm happy to spend time answering.
My suits are generally in various shades of grey (from pale to charcoal) and navy blue, with a beige/cream one too. Most of them have patterns though, mostly fairly subtle but some stronger ones too. Coats and other outerwear are in greys, dark browns and navy, mostly. I do have some black evening wear too.
My odd jackets have much greater variety, from cream linen to aubergine corduroy with everything from brown plaids and seersucker in between. I recently ordered a couple of new jackets, one in a mid-grey with blue overcheck and another in a green with a mustard overcheck, too. Odd trousers are generally solids or near-solids, in a large range of colours: greys, off-white, tans, russets, blues, dark greens and so on.
Shirts are a mix of whites and blues with various patterns and shades, and a few pinks, lilacs and other more obscure shades. Socks & scarves are pretty conservative, but I do have some quite eccentrically coloured & patterned ties amongst the more sober stuff.
Leaving aside my own wardrobe, if you look through fabric books, you can find some extraordinary colours and patterns. My jazziest suit is a midnight navy with neon purple tramlines, but in fabric books I've seen bright pinks, purples, oranges and other colours you rarely see as part of menswear these days. In other eras, they were more common, and there are still plenty of cultures & venues where you can wear them.
So I don't think there's an absolute association of colour with gender, but I do think certain complexions suit certain colours and I do think there's a generally accepted colour vernacular in various contexts that it's wise to be aware of. Even if you ignore it, it's best to know
what you're ignoring and for what effect/reason.
At its most basic, this includes conventions such as darker/richer colours in winter with paler/brighter ones in summer, or dark suits in formal business contexts, or vivid colours/patterns for holidays. For example, think of those brightly coloured floral Villebrequin swimming trunks that were all the rage a while ago. Definitely not traditionally male, but completely acceptable for male swimwear.
A conventional "masculine" tailored wardrobe designed for traditional business would include lots of dark grey and blue suits, with white & blue shirts and fairly dark ties. Sometimes women ape these colours when they're in conservative professions by way of blending in, but I've also seen women deliberately/consciously choosing more conventionally feminine colours (pinks, reds, brighter greens, lilacs/purples, french blues, whites/creams) in order to carve out a separate identity/role within their workplace. It's all about accepting the vernacular (as by definition, most people know it, at least unconsciously or through cultural osmosis) and then playing with it (or not), depending on what your personal needs are.