Problem/Motivation
This block has many issues as outlined in https://www.drupal.org/project/drupal/issues/3174990#comment-16035695
1. Has a block_count config which does nothing. This will need an update path to remove the config, etc. See #3223555: SyndicateBlock has unused block_count configuration
2. Config dependencies - the block should depend on the view.
3. Access controls - The block shouldn't render if the view or display doesn't exist - what happens if someone renames the display from feed_1? Should we just hide the block in those cases?
4. Cacheability - the block render cache needs to depend on the views config.
5. The block breaks if the url changes in the frontpage view #3174990: Test that SyndicateBlock works when views disabled
6. It has a configFactory class property that isn't used.
Proposed resolution
Deprecate the block with no replacement
Remaining tasks
Do it
User interface changes
Block removed from Olivero
API changes
SyndicateBlock is deprecated
Release notes snippet
SyndicateBlock is deprecated