It was agreed on the release call 10/10 that we will either remove the code or disable the paths to getting the previous formatted text processor from functioning. AntiSamy low would be the default as this matches closest with the previous filter.
If someone has the property
Then a warning should come up in the logs saying that the legacy content cleaner has been removed.
The configuration attributes were removed in
SAK-25270 so if someone tries to actually set this (to true) it won't work.