He’s thrown 350 innings over parts of 3 seasons. That’s a part time player, not a rotation anchor. He’s need an innings limit in 2018, probably even if he’s healthy.
We're not nominating him for ace here, but your language is seriously misleading.
As for the 350 innings over parts of 3 seasons, let's break that down. In 2015, his age 22 season, he came up at the end of May and then threw 21 starts -- no durability issue there. He pitched well, too.
The following season, for reasons I forget, he started in AAA, and came up at the end of May again. After a good first start, he pitched poorly over his next five starts, culminating in a 9-run horror show at Tropicana. He got sent down, started two games in Pawtucket, came up after the ASB and only missed one start the rest of the way, again pitching very well through the second half.
Last year, he was one of the better pitchers in the league before his knee problem sidelined him in early June. After he returned, he was not as good, and in retrospect clearly wasn't 100%, but he wasn't terrible.
Rodriguez in his brief major league career has had one truly terrible month, June 2016. Before that month he had a 3.81 ERA with 101 K/37 BB and a .697 OPS allowed in 127+ innings. Since his return after the All-Star break that year, he's had a 3.85 ERA with 229 K/78 BB and a .692 OPS allowed in 215 innings--despite being evidently hampered by injury for a substantial piece of that stretch. Who knows how quickly or completely he can come back from surgery. But suggesting that he's inherently or essentially a marginal pitcher is just willfully ignoring the evidence.