Purchased Photoshop Elements 2020 earlier this week and downloaded it successfully, albeit a 3 hour process. Unfortunately I am unable to download CR3 Raw files from my Canon 90D camera. Dropdown box states "Media files weres kipped because they are not supported".
I did wait to purchase the 2020 version and did so when I saw your post dated Feb 2020 listing various Canon camers'a which are now supported. Thankyou.
PSE 2020 is downloaded with the ACR module 11.3 while your 90D requires 11.4. So you have to update to the latest 12.0 version from the menu Help >> Update. You should be prompted to download this update automatically next time you open Elements.
3 hours seems unusually slow for a download, so I am afraid the update will be slow too.
Go to the Editor and under the Help>About Plug-in>Camera Raw screen, what version is listed? Your camera requires Adobe Camera Raw 11.4. I think Elements originally shipped with 11.1 [Edited: Michel is probably more accurate than me] and has now been updated to Elements 12.0. So your files should be recognized if you have the updated version installed. If not, go to Help>Updates and see if it is active. Normally, the updates occur automatically but can take a few days to kick in.