So, you get the latest version and regular updates of Bridge for free.
I am a fan of the organizer, but I also do use Bridge when it can help.
If you read the forums, you'll also discover that for PSE2021, there is an experimental feature called 'Save to the Cloud' which is progressively made available to some PSE2021 users. That new features requires that the free Creative Cloud be installed to get a small Cloud space allocation, so it may be installed automatically when you install PSE2021. And you'll only have to install Bridge from that limited and free Creative Cloud app.
Anyway, be ready for a lot of changes in the current versions of PSE and Bridge!
Also be sure to have the installation files and license key to re-install your old LR version.