Filters work to receive new content that matches, but content that stops matching does not disappear (Kanban style view test)

I run across this weird and imho, buggy behavior, when trying to create a Kanban board. Basically, four views of the same table, each view filtering for a single List Option of column task
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When I change the Task

the “card” gets duplicated, because it appears under the It Preparation task filter, but it did not disappear from the Training task filter