Basic voltage/current regulation with MOSFET, cannot fully close current controlling MOSFET
In Falstad’s sim, you must define the Beta (RdsOn) and not just Vt . You had the default beta=0.02 which is a high Ron like 4000 series CMOS. The properties allow you compute RdsOn for the Vg, Vgs(th) and Beta value.
Also all IC’s are ideal voltage sources, so to simulate current limit add 220 to output or if CMOS 1k and inside if using a closed loop.
Logic would be 300 ohms in series for 4xxx 50 Ohms for 5V logic and 25 Ohms for 3.3. logic family. if you cared about load capacitance and ESR etc, you add those if that is important.
Normally I might choose Vout for 15V max and not divide 19 with 10k series to 2k shunt.  The FET has a body diode option which don’t need to add since you defined
So you can model any RdsOn by selecting Vgs, Vgs(th) and use Beta somewhere between 1 and 50 for starters.