I decided to take a look at Grier's drafts since becoming GM in 2016, just to see how horrible he was at picking talent. Turns out he's not that bad, at least in my humble and uneducated perspective. Here is each draft class, along with my thoughts on them.
2016: Tunsil, Howard, Drake, Carroo, Grant, Jordan Lucas, Brandon Doughty, Thomas Duarte
I think you have to give this draft a "A" for obvious reasons. I think we all questioned trading up for Carroo, who ended up being trash. But 4 of the top 5 picks have all been very productive, and one of them netted us three other high picks.
2017: Charles Harris, Raekwon McMillan, Tankersley, Asiata, Godchaux, Vincent Taylor, Isaiah Ford
We'll refer to this one as Grier's Terrible, Horrible, No Good, Very Bad Draft. Godchaux was productive, but that's about it. Taylor, eh. Ford, eh. Tankersley started off well only to fall down a hole. F for this one. Zero stars. Do not recommend. There were obviously better players to be had, and we didn't pick any of them.
2018: Minkah Fitzpatrick, Gesicki, Baker, Smythe, Ballage, Cornell Armstrong, Quentin Poling, Jason Sanders
I have to give this draft class an "A". You can argue that Fitz isn't on our team, but he was a great pick talent-wise. Gesicki has been awesome, and Baker's been good enough to be extended. Of course, the crown jewel of this draft class is Ja$on $ander$, the best kicker the Dolphins have ever had, who was also extended.
2019: Wilkins, Deiter, Van Ginkel, Isaiah Prince, Chandler Cox, Myles Gaskin
I think we can give this one another "A". Wilkins hasn't quite been the dominant guy in the middle we were expecting, but he's definitely been good. He improved, as expected, from 2019 to 2020, and improved in the last half of 2020 over the first half. Deiter didn't do a lot initially, but he's shaping up to be a solid starter. AVG has outperformed his draft position, and so has Gaskin. We now have four starters from this class.
2020: Tua, Jackson, Igbi, Hunt, Raekwon Davis, Brandon Jones, Kindley, Strowbridge, Curtis Weaver, Blake Ferguson, Malcolm Perry
Can't really grade this one yet. If Tua ends up being a legitimate franchise QB, then that'll weigh heavily in favor of an "A" grade. He had a rookie-like rookie year, with highs and lows, but he looks ready to make a good jump this year. Jackson and Igbi look like reaches right now, but sometimes it takes a while for the light to come on. Raekwon Davis had some rough spots in 2020, but had more good or even great spots, making the NFL All-Rookie Team. Hunt is trending the right way and looks like he'll be solid. Jones, Strowbridge, Ferguson, and Perry will likely all make the team this year and will contribute, which is good. Weaver is gone.
While we can certainly argue over who should have been taken instead of Jackson and Igbi, the jury is still out. We can also disparage the whole 2017 draft, which was horrible, but I don't think any GM hits on all his picks, or even the majority of them. I could be wrong on this, as I haven't looked at the work of any of the other GMs. I just feel like any year where we're able to get at least a few starters and then some contributors is a good year, and the only year that didn't happen was 2017.