@LuigiMaster
Those are not guranteed tho. They are all mixups, as stated before. If Luigi players go for a grab after d-smash or up-smash, you can just roll away or spotdodge, or in the case of up smash, just jump away. Also from my knowledge Fox players can actually shield before the second hit of d-smash if they DI down quickly and shield (shields come out on FRAME 1). If Luigi players attack, Foxes can just hold shield and counterattack and possibly get an even bigger punish on the Luigi players, which really sucks. As I said before, d-throw > up-b is definitely not safe at low percents because it does not send opponents far away from Luigi, and Luigi is stuck in million years of endlag. So definitely not safe. People keep mentioning mixups as reason why fox gets combo-ed hard, but what Luigi thrives off of is NOT MIXUPS, its GUARANTEED combos or extremely safe mixups.
Also, doesn't d-tilt send you too far away for jab? And jab cancels are also mixups that can be avoided by quickly spotdodging, shielding, or rolling away from my knowledge. If you are referring to d-throw > d-tilt for the trip chance, the trip is really unreliable and completely RNG dependent, which is why I see most Luigi players not going for that option.
All of the mixups that you mentioned really only work on low-mid level players or players that are really not familiar with Luigi. Basically its really only effective against the FG-level or similarly-leveled players (except for jab cancels, which is probably Luigi's most reliable mixup options).