[2020] Stuck at 30%

This is usually caused by either mods that have not been updated to work with the 2.8 patch, or hardware plugged into the computer such as game controllers or joysticks.

Do either of those apply here?  

Please do a full **clean** re-install:

- move any valued save games elsewhere, and user_empire_designs.txt from /Documents/Paradox Interactive/Stellaris/ if you have made any custom empires or races.
- "uninstall" in Steam-Stellaris
- manually delete both the Steam/SteamApps/common/Stellaris AND Documents/Paradox/Stellaris folders
- re-install game in Steam, run a Steam Verify when done.
- add stellaris.exe to the exceptions list of your antivirus app; ESPECIALLY if you have Windows Defender, add it to the Ransomware "Apps Allowed Through" list.
- start the game with no mods active and test

In particular you need to make sure there are no files or folders left under either the Steam Stellaris or Documents Stellaris locations, before installing again.  

DXDIAG is a program you run from a command prompt or the Windows start menu 'run' dialog box (or 'search programs' in Windows 7 or later). After running it will open a window and start collecting info with a progress bar in the lower-left corner. When it completes click the 'save all information' button and save it to a file then attach that file here.

Please attach your Documents/Paradox/Stellaris/settings.txt and pdx_settings.txt .
From your Documents/Paradox/Stellaris/logs/ folder, attach system.log , error.log  

I've now seen another report of modest numbers of mods taking a long time to load with this game now. Whether this is a game or a launcher issue I'm not sure but I'd incline to the launcher.  

You are welcome to add your voice to the others reporting this to the launcher developers here:

New launcher version : 2020.14

Launcher time again - This time the release is 2020.14 and it's a bit of a maintenance release as we are hammering away at some design changes in the background. Changes Improvements to renewal of authentication tokens - In short, you'll stay... forum.paradoxplaza.com