Is this whole having to use Star10 a new thing to 1909
No, Start10 always needed for Windows 10. For Start menu too look like Windows 7 or modern style Start panel.
On the screenshot, that look strange to me, did you exclude Explorer.exe in "Per application" setting? If not, please try the purge and reinstall steps : https://forums.stardock.com/486023/windowblinds-support-faq#reinstalling
Just to make sure, re-download the latest version from your account. Reboot after the purge, reinstall using the one you just downloaded, reboot again after the installation and retest. Report back here.
Stardock Community Assistant.