No idea what to do with CSGO keys

CS:GO keys won't die anytime soon, and if they ever do, you'd know well in advance.

wait for sales, then trade. or just market them and buy games with wallet.

btw, tf2 is almost 10 years old and its keys still work. i doubt csgo economy would die suddenly ¯\_(ツ)_/¯

betting sites use to take keys, you could trade it for better gun skins or use them to open crates that belong to those keys and hope for a knife or a skin you want! all else fails you can give them to friends!

Well, in my point of view, you have just a few keys, justa few games and just a few titles on your wishlist, I think you should sell them or trade them for games that you want !
I think that sell them and wait for some good steam sales is a better choice, because when you trade people ask for a good amount of keys for games that doesn't worth that much, but that's how trade works... one will always have the better deal and the other you be left with the sh*t part ¬¬

its easy you buy stuff on sale that you want with them from cheapest row region available for them.
Keys = Price without Fee + Profit the Trader asks for.
Lets take as example Duke Nukem forever and Falchion Case Key atm around 2,46€ = 2,15€ after Fee. First my Region then the Cheapest Row Region:
EU:
Without Sale: 35,95€ / 2,15 = 16,72 = 17 CSGO Keys
With Sale atm: 7,19€ / 2,15 = 3,34 = 3,5-4 CSGO Keys.

Cheapest Row Region should be Norway: Currency converter says 2,15€ should be 19,77 Norwegian Kronen

Without Sale: 270 NOK / 19,77 = 13,65 = 14 CSGO Keys
With Sale atm: 54 NOK / 19,77 = 2,73 = 3 CSGO Keys.

To find out which is the Cheapest region u use steamdb.info: https://steamdb.info/sub/15361/
As you see it pays out to buy on Sales, and even more to look always for the Cheapest ROW Region.

Keys can also be used to buy Humble Bundle extras, which can be far cheaper than the Steam Sale prices for some games. But always use a reputable seller/trader, as you are not going through the protected trading system.

You can use keys to buy good bundle games for cheap or you can sell them for steam wallet and then wait for big sales to use that money. It's up to you.

I don't think CSGO is going to die anytime soon, but if you're worried about it you could follow its playerbase status over here and if you start seeing drastic decline in players it would be a good time to sell all of the keys.