1. You need to set up NAS and downloading software - that is not as trivial or common as HN audience assumes :)
2. You need a reliable and safe source of torrents. They may be paid or invite only, or may be super scammy and unrealiable and mine crypto etc etc
3. How safe do you feel in your jurisdiction/location at running plain torrents. Here you get notices and sometimes strikes / actions pretty quickly, so now we are talking at least a VPN, which is next layer of setup, configuration, possibly price, possibly its own threat vector as commercial VPNs are scammy, your own VPN is non-trivial to setup correctly.
etc etc etc :)
Agree with 2 though.
If you want to go down this route (and you use *arr) prowlarr is a must have to avoid wasting time copying configs between the *arr.
I download remotely, then have local snag from remote. Local is a custom server, on Pi, on an isolated network (with its own cable modem).
Once the Pi receives a file, it transmits it over a modified optical link, where I cut the receive line on the sending nic board.
Checksums are simple, and sent via email back to the remote server, checked, and I am alerted of wrong.
My media PC is all that is connected to that local network.
I've considered getting back into it occasionally.
Why: Convenience and access. From having everything on Netflix a decade ago, to now having almost as many subscriptions as I used to have cable channels, it's a pain (let alone a cost) to install dozen apps on my phone tablet TV roku etc. Their quality varies WILDLY. The user experience ranges from pretty decent to seemingly user hostile. I've recently watched a set of seasons of a show pirated a decade ago, then last two seasons on actual subscription service, and it sucked: app would not let me download to SD card, had to take precious phone storage. Subtitles were 2 seconds behind with NO way to adjust. Fast forwarding was wonky and basically unusable. And best of all, it auto deleted itself 48hrs after downloading so I had to keep redownloading same stuff over and over. Brutal!
Why Not: As explained above - It's pricey and time consuming, there's a fair amount of risk in pirating, and technology seems to keep changing. I made a post about that a while ago, but I'm no longer at a point in my life where every 6 months I can spare the time to fully rebuild and reconfigure and troubleshoot a stack from sabnzbd and nsbmatrix to udirwioay and fewiap and fdsjei, and then 6 months later again to fdwjieo and wearp routed through wefheio and zxcnzxcv. I have a friend who keeps urging me to set it up because it's so easy - oblivious that whenever I try to use his helpful "how to", a) It's 3 pages long b) it is missing about 10 pages of details and c) It's already out of date so it's "do that, but none of that actually because these days now the cool thing is ____" :D