I have the exact setup shown towards the end of the article - HTPC and K400 keyboard/touchpad. I have tried all "smart" platforms in the past, and this setup is an order of magnitude better in everything. I used to have issues where a specific content provider doesn't have an app for my type of smart TV[1], this is no longer an issue because I just use a browser to access anything. And I can browse the web when I'm not watching something[2] (in fact I'm using my HTPC right now as I write this comment).

The only change I had to make starting from a "standard" Linux UI is bumping the screen zoom level to 150%. This may vary depending on your TV size and how far your couch is from your TV.

Building the HTPC was very cheap, I just boughs a horizontal form-factor case, and used spare "donor" parts coming from our household PCs after upgrades.

[1][2]For comparison, the only streaming platform that had all apps I wanted was Apple TV, but that one doesn't have a browser.