rune

I'd even recommend encryption for non-laptops, it's less about IF they get stolen and more about WHEN the hard disk fails, you don't need to worry about all of your personal data being immediately available to anyone who plugs in your failed disk (whether RMA'd or electronics disposal). Before diaposal, if you can, run cryptserup erase to scrub the encryption keys.

You need to figure out your threat model. Is it that you don't want YouTube to connect you to what you watch? Is it okay that YouTube knows that soneone at your IP watched the video? What about intermediaries knowing who you are or what you watch?
Most of these options just avoid using Youtube's UI, which at best blocks cookies, but reveal your IP. Others download, which is about the same.

Now they are all really scammy. I haven't found a good code in years. All those sites do is forward you to the site with a referral link, if you buy something, coupon code or not, they get paid for the referral (and possibly future purchases you make).

Best I can suggest is to attack their business model. Open those sites in a private tab, copy/paste the codes to your normal browser.

Been using Garage for non critical stuff for a while, no problems.