Not really. Primarily, Dyson had shoulder surgery, not the more standard Tommy John elbow surgery like Pineda in 2017, so the recovery is less predictable. Plus Pineda had his surgery several months earlier -- July 2017 compared to October 2019 -- so his return was expected sooner. Plus Pineda is several years younger than Dyson.
But perhaps more than all of that, SP are in greater demand than RP -- partially illustrated by the salary differential. It might be worth it to commit early to a $10 mil guy, but probably not for a ~$3 mil guy. (And indeed, I can't recall any relievers on Dyson's level signing a rehab contract like that, while I can think of many SP.)
I feel for Dyson, to pitch through pain like that for an extended period, but if I were GM I’d do the same as Falvey.
There’s no telling how well Dyson will recover from shoulder surgery, and relievers are so volatile from season to season when they are healthy.
I hope Dyson heals up and is ready to go in 2021, but I wouldn’t try to pull a Pineda with him to find out.