Use Playlists to create collections of video or audio files in Microsoft 365

I hear ya...it's not easy. What might work out better for you is starting with a basic SharePoint list and including columns for the description and links to the video and PowerPoint. You could then use some list view formatting to make it look the way you want. There's even a sample out there you could use (or customize): https://github.com/pnp/List-Formatting/tree/master/view-samples/video-gallery

FWIW, I maintain a site for our M365-related trainings. For each workshop, there's a page like the one below that has an overview, link to sign up (through another system), resource links, past session recordings and blog posts. The session recordings are stored in a document library and tagged with the topic (e.g.: SharePoint, Teams, etc.) and type (course recording, tip/trick, etc.) and then I use a Highlighted Content web part that filtered to the page topic. Same thing with the blog posts, but those are "news posts" from the site pages library (also tagged with the topic). It's worked out really well and with the filtered HCWPs, all I need to do is appropriately tag the videos and blog posts as I upload or publish them.