They’ve finished 3rd-4th-4th-3rd-2nd-5th and currently a few wins clear in 5th.
They’re not winning a title unless they get a big investor, but I don’t think Wenger is holding them back.
If a rash of players started wanting out, you’d make the call. As it is I think it’s better to hold ground than go through what Tottenham, Man U or Liverpool have been through in the past 3-4 years, chopping and changing, up and down, never getting much closer to the chocolates. If the finances can’t stretch to a few more players now, sacking 2 or 3 managers and dropping down thr ladder won’t help.