Silman can take as many guys who have been chessing on chess.com for years making no progress as he likes and easily prove himself wrong.
Why is chess taken so seriously?

Chess is serious because it can win you an Ivy League school scholarship and requires deep mental thought.

the only thing that spoils these games for me is bad sportmanship.
Definitely

If an instructor is chosen that fits your criteria, 10 years of study and training will make anybody a master. Memorization alone should do the trick. Could very well be 1 instructor is not to your liking. He won't be for you. That's alot of hours at 8 hours a day.

Reinforcing 011s....Point that chess is a skill that can be studied and learned, built upon like many of life's skills.

Yeah, being good at chess doesn't mean you're smart. It means you're good at chess. I mean, I got A's in calc 1 and friggin' terrifying historical geology and I most certainly suck at chess.
There are many games of pure skill that are not taken seriously by anyone except afficionados. Chess is by now sufficiently universal (it is almost surely more widely played internationally than any other top game) that even those who don't play view it as at least a semi-serious past time.
Part of the seriousness stems from the publicity that the early world champions brought to the game. Then later from the concerted effort by the USSR to make chess the pastime of the common people and then to use it as propaganda for communism. And that in turn spurred the US to take it more seriously as a kind of strategic response. More recently China has decided to focus on international chess (despite having a long tradition of xiangqi or Chinese chess) as well as weiqi/go as a source of prestige (not unlike the early USSR). These big players lend weight to the games and the "glamour" and publicity attached to the most visible champions from Kasparov to Carlsen have further enhanced the status of chess. And in general, when people do well at a high status enterprise they take it more seriously.
Just think about the fact that checkers was once (mid-nineteenth century) probably as popular or more so than chess in the USA, while neither was prestigious. But the common people don't think doing well in checkers today is that serious or interesting, though its greatest practitioners also had great skill.
I'm not so sure that seriousness is the issue. It is losing sight of the fact, that for most of us, it is supposed to be recreation. Serious is great when it is paired with exercising the imagination and fully exploiting resourcefulness. Serious is maddening when it only supports mediocrity. If you are really going to get serious about the Colle or Caro Kann then why play chess at all? Why ruin games for everyone else? Why not try Chinese checkers and make everyone happy?
A serious gambit or sacrifice is fun. Serious opposite color bishops or serious 16 pawn endgames are infuriating.
I have to applaud Thrillerfan post #11 in general, however, I have to amend or disagree with a couple of points, I would extend the Bridge postition to include miss calls or plays by your partner (or yourself, from your oppostions or partners viewpoint), and regarding Scrabble, the skill in how to play an all vowel or a no vowel rack, how to restrict your opponent or leave an opening for him, knowing that if he plays there he will leave you a position to score big, levels the temporary "bad rack" and ratchets up the skill at the higher levels. I pesonally take all competitive games seriosly, otherwise there is no point, each game, win lose or draw, can be a learning experince (more so with reviewing and assimilating a loss), but you need to enjoy them and revel in each and every one as well, I sometimes get a bit annoyed with myself if I make a mistake where I should know better otherwise the only thing that spoils these games for me is bad sportmanship.