Tab unloading despite not too many active tabs

there seem to be only about 20 active tabs before librewolf starts unloading tabs. free tells me that there is not much free memory but isnt that mostly taken up by caches?

gesamt benutzt frei gemns. Puffer/Cache verfügbar

Speicher: 7523908 6256600 614944 39412 652364 925784

Swap: 9227464 2757632 6469832

smem however tells me that only half the ram is used