Unless he fucks up completely and repeatedly crashes out, Sargeant will keep his seat. James Vowles said that the plan was always to have Sargeant racing in 2024 and the reason he's racing this season is they had an opening and thought it was better to give him a "practice" year in F1 than another year in F2
Kicking a driver out because they didn't do well in their rookie season always sounds like the kind of insane move that not even Helmut Marko would try