In this Spot I don't really understand the results of the solver I use.

Preflop Ranges:
SB-3bet vs BTN: AA-66,AKs-A7s,A5s-A4s,KQs-K9s,QJs-Q9s,JTs-J9s,T9s,AKo-AJo,KQo,[50.0]55,T8s,98s,ATo,KJo[/50.0],[25.0]44,87s,76s,65s,54s[/25.0]

BTN Call: 77-22,AQs-A9s,A5s-A2s,KQs-KTs,K8s,QJs-QTs,JTs,T9s-T8s,97s,87s-86s,76s-75s,65s-64s,54s,[90.0]99-88,A8s-A6s,K9s,Q9s,J9s,98s,AQo,KQo[/90.0],[75.0]JJ-TT,K7s,AKo[/75.0],[50.0]QQ,AJo,KJo[/50.0],[25.0]K6s,Q8s,J8s,T7s,96s,53s,ATo,QJo[/25.0]

SB has around 55% Equity and around 35% Toppair+ so a very strong Range, I believe.
BTN has only 26% Toppair+ but a lot of weak Hands which completely missed (~ 30%).

I would expect the solver to use a small size with a high frequency. Folding out a lot if BTN's air while also getting some protection and value with his marginal hands such as A3 or TT. However in my sim the solver only cbets around 20%. Sure the board is not as good as A72r because BTN has more Hands which connect with the board, especially low suited connectors, but BTN also has more air like T8 etc.

Once the SB checks BTN stabbs around 33% with a bigger sizing, which makes sense because SB's Range is well protected.

So how come the solver checks so frequently although we have quite a decent Range advantage. In practice I see a lot of players differ from that and expecting to see a lot more cbetting. How would you exploit that?