Maybe FreshRSS with some extensions?
I saw a recent commit to fire an event when saving a favorite, so probably you can get an extension to send the link to something like archivebox for the pages you favorite.

I’ve just fiddled with an already created extension, but they seem fairly simple to create your own easily.
Of course you can inject JS so you could make it more complex if you want.

With invidious and in FreshRSS I use the youtube extension to use the embedded video player, you just need update this part of the code https://github.com/FreshRSS/Extensions/blob/master/xExtension-YouTube/extension.php#L153-L163
It easy just to replace for this:

    public function getHtmlContentForLink(FreshRSS_Entry $entry, string $link): string
    {
        $domain = 'www.youtube.com';
        if ($this->useNoCookie) {
            $domain = 'www.youtube-nocookie.com';
        }
        $domain = 'invidious.personal.com';
        $params = 'quality=dash';
        $url = str_replace('//www.youtube.com/watch?v=', '//'.$domain.'/embed/', $link);
        $url = str_replace('http://', 'https://', $url);
        $url = $url . '?' . $params;

        return $this->getHtml($entry, $url);
    }

The only change is to use $domain = 'invidious.personal.com';
And add the parameter quality=dash

Seems there’s also this one https://github.com/tunbridgep/freshrss-invidious
but haven’t tried it

That’s a weird read having in mind I had to move to Wayland because x11 had severe screen tearing. I would have guessed Wayland had better support.

I don’t think there are services like that, since usually this means deploying and destructing an instance, which takes a few minutes (if you just turn off the instance you still get billed).
Probably the best option would be to have a snapshot, which costs way less than the actual instance, and create from it each day or so yo run on the images since it was last destroyed.

This is kind of what I do with my media collection, I process it on my main machine with a GPU, and then just serve it from a low-power one with Jellyfin.

Start by learning docker, you don’t have to selfhost anything yet, just learn to run a container, specially to run automated stuff. Then learn to build the images and run docker compose.

Also you could start checking any form or infrastructure as code. I usually hear about ansible and nixos.
This helps having a way to redeploy your services in any hardware easily.

Does it apply it to all feeds? Or can it detect what feeds are actually Youtube ones?

Weird, it didn’t ask using firefox and ublock origin.
I don’t have all lists active tho.

Why do you need the files in your local?
Is your network that slow?

I’ve heard of multiple content creators which have their video files in their NAS to share between their editors, and they work directly from the NAS.
Could you do the same? You’ll be working with music, so the network traffic will be lower than with video.

If you do this you just need a way to mount the external directory, either with rclone or with sshfs.

The disks on my NAS go to sleep after 10 minutes idle time and if possible I would prefer not waking them up all the time

I think this is a good strategy to not put additional stress in your drives (as a non-expert of NAS), but I’ve read the actual wear and tear of the drives is mostly during this process of spinning up and down. That’s why NAS drives should be kept spinning all the time.
And drives specifically built for NAS setups are designed with this in mind.

IIRC they mentioned is next to impossible without actually processing the video and guessing when then ad stops on your client (since the ads will change per user, so it can’t be done on a server for all users)

Yes, most podcasts are hosted outside of your podcast player and distributed via RSS (even if this is Spotify which already hosts music).
So when a service has the podcast it means it lists the response from the RSS feed, but usually they just copy the text data, including the URL where the actual audio is stored.
This audio is served by whatever other service the creator of the podcast uses, which means you’re a free user to that service even if you pay for Spotify, which means the wonderful benefit of ads.

And these are ads you can’t block since they’re included in the audio stream (yay! /s).
Podverse (the player I use) mentions this as an issue when creating clips of the podcasts because they can’t know how much the timestamp has been offset by those ads, so your clip probably only sounds good to you.