Linux

I ran into this too. My bad, I included a screenie of the menu used to fix it but didn't explain it proper.

1. Open Kodi's Settings > Skin Settings > Customize Home Menu.
   On this Screen, you'll see two panes. The Left one are the items on your homescreen, the right one are all their settings:
   

For me, the Videos Menu isn't useful, so I scrolled left until the the little 'X' button has highlighted and deleted it.

2. Next up, the Movies item:
   Hover it and scroll right a couple of times till you reach the right pane.
   Select 'Action' and you'll see a popup:
   

3. Scroll down to Add-On > Video Add-On > JellyCon > Jellyfin Libraries > Select your movie Library (In my case it's just called Movies) > "Movies - Genres" (You might have to scroll down a bit to reach this option) > Finally select "Create menu item to here".

4. After you're done with this, go back to the skin settings, scroll down to the 'Extras' section.
   This eluded me for a while, but this skin doesn't make it very clear when there's menu items out of view, so while the settings menu looks like it ends at the "Video / Music OSD" category, you can actually scroll further.
   Keep scrolling down until you reach the 'Extras' section.
   
   On that menu, make sure "Enable forced views (experimental)" is enabled, this will be useful in a sec.

Now when you return to the home screen and hit the 'Movies' item, you'll be thrown directly into the genre selection!

Now, the genres can only be presented in a list unfortunately. It looks a bit goofy with the blank poster on the left.
Sorry about this. Since I have my movies shown all at once in alphabetical order, I hadn't noticed.
If you'd prefer to forgo the genre selection and just get all your movies at once like I do, check the 'Extra tips' at the bottom of this post.

Anyway, select one of the genres and you'll be thrown into another list view, hit Left and you'll open the View Settings.

From here, customize your view as your like, there are many views to choose from so you can finally escape from that dreadful list!
If you're curious, the one from my original poster is called "Poster Flix V2" with the "Clearlogo" option enabled.
Just like the settings menu, there's more options that it seems, make sure to scroll down!

After you're happy with it, open the view menu again (depending on the "View Mode" you've selected you might have to hit the Up arrow instead of Left this time around. Enable the 'Lock View for Movies' option.
Now your movies will always use the style you've selected.

After this setup, your workflow should be:
1. Open Kodi
2. Select Movies
3. Select Genre
4. Play Movie

Much better than before right?
Hope this helps!

Extra tips:

• If you want don't want to have the genre list on your movies, repeat steps 1 through 3 but choose "Movies - Show All" instead of "Movies - Genres" at step 3.
• If you also want to do the same to your TV Shows, repeat steps 1 through 3, but choose the 'TV Shows' menu item on step 2 and your Jellyfin TV library > 'TV - Show All' on step 3.
  You can customize your view for TV Shows, Seasons and Episodes separately. Simply open the View Options menu when browsing, customize your view and choose the 'Lock View' option, just like you did for your movies.
• Want to have the Next Episodes view on your homescreen like I had on my original post?
  Go back to the menu from Step 1, scroll to the item you want, scroll right to reach the right pane, on the Widgets section select Widget 1 > Widget 1 again > Add-On > Video Add-On > JellyCon > Custom Widgets > Scroll down and choose "Episodes - Next Up" (or any other widget from the list you want) > Use as widget > Customize the name if you want and hit OK.
  Customize the view settings like if you'd like (I was using the 'Landscape Widget aspect' on my original post)