It's strange how suits became a standard for government officials, big business and everyone that want's to look "serious" in all countries over the world, it shows how the western culture conquered the entire world.
It's as if a leather jacket, white T-shirt, jeans and Doc boots had become the mark of tedious conformity.
A suit is a uniform. In a more practical sense, it's a means of directing creative energy away from irrelevant causes, such as self-expression, and enabling you to put undivided focus on your work items, the processing of which benefits the business.
If everyone is in a suit, there can be no games to out-dress the rest of the playing field. The only differentiator is the price of the suit, and that story-line unfolds neatly along the sub-ordination divides. The CEO wears the most expensive suit.
Being the tech-oriented minion, you can get away with wearing a just-so suit, which is just fine by you as well. Honestly, who wants to fashion-shop for a freaking suit? The suit surely has to be the most drab and boring garment in the history of clothed mankind.
I bought a Gieves and Hawkes[1] suit for my wedding, and the whole Savile Row[2] experience was wonderful.
I don't need to wear a suit every day, or even every month, but if I find myself in a situation where I do need to, I know exactly where I will be shopping for one.
It's all a lot of fun. I used to really enjoy shopping for suits, shirts and accessories when I was in a job that required me to wear a suit every day.
'Cause I'd rather invest it.
I guess for one-off things like weddings, fine, but other than that, not my thing.
Try to take out a mortgage dressed in a T-shirt, shorts, and flip flops, and then try to do it dressed in a suit.
It sucks, but it's a real thing.
We tend to think of gold valuable because it is pretty, and because it's pretty we wear it, which gives it market value.
In reality, this is not untrue. But more importantly, we value gold because of scarcity, and that gives this not ugly looking metal value (there's not enough gold in the world for everyone, after all). And because it is valuable, we think of it as pretty and wear it, because it shows a certain status. This is why we somehow perceive fake gold so negatively, not because it's aesthetically different but because it's worthless. We hide this fact with words like one is 'authentic' and the other is not. While really, they look the same, and they're both arbitrary metals, but one is scarce and thus not cheaply available for all, while the other is.
In fact, quite some time ago aluminium shared the role of gold, it was even scarcer (before factories produced it) and more expensive. You can find anecdotal evidence of this, e.g. Napoleon holding a banquet where the most expensive cutlery was made of aluminium for the special guests, and the regular guests had to use mere golden spoons. All of that ended when producing aluminium in a factory was discovered and the price plummeted from hundreds of dollars per some unit (can't remember) to mere pennies. Today you'd look mostly foolish wearing an aluminium chain, mostly because it's simply way less scarce.
That's why I was reminded of it by your comment about suits. It's likely true that we consider suits to be serious because they're 1) uniforms and 2) simple, hard cuts
But at the same time, that's just today's fashion. In the early days of suits they were colourful, they had rounded shapes, they were also used as uniforms etc.
In other words, I think what actually makes them 'serious' is the people wearing them. You can find a garbageman uniform, or make one, that's cleaner and more modern and slicker than a suit. But we'd immediately attach negative connotations to that uniform. In the same way gold isn't necessarily the prettiest thing, but because of meta-reasons (e.g. it being expensive, or worn by cool people), it's desired. Suits are likely pretty similar. It's the fact that important people wear suits that inspires the seriousness.
Anyway, that's just one hypothesis of course :)