My attitude towards prequels generally over the past 20 years has been mostly negative but that has nothing to do with the idea of one itself, rather its execution.
With relation to Trek; there has been 1 attempt that resulted in cancellation and 3 “films” that have resulted in a semi-reboot that to me seems more aimed at and made by a star wars fan. So at this point in time I have many concerns about the setting of this new series, but I feel more optimistic towards Discovery than I was towards that other “show”. Optimistic (cautiously) in that they have not decided to set it on a ship that did not exist previously in canon.
That was the major problem with that other show was that no amount of explaining away can possibly reconcile that the NX-01 did not exist in canon. There was an established line of ships named Enterprise referenced on numerous occasions that was simply ignored. I believe that the studio made a (simple-minded) edict to B&B that the next show must be on an “Enterprise” so if that was indeed a constraint that they had on them then that is fine, but it wasn't very hard to do even some cursory research for how to make a show on an enterprise in a previous time-frame, a quick google search would have done the job. If that constraint wasn't there, then simply making the NX-01 (despite the other criticism's I have on its design) a ship with a different name would have solved such a fundamental problem.
But I digress..
There are pro's and cons to sequels and prequels. I think the former is certainly easier than the latter, but in the context of trek there is equal potential in both. I personally favour the sequel option as there is less risk of tripping up and undermining canon either by accident or by willing ignorance (motivated by being uncreatively lazy like B&B did with that other show). There is freedom with a sequel in that the universe can be built upon rather than built within a pre-existing framework.
But so far with discovery, the fundamental premise that I know so far has not fundamentally contradicted canon so for me the first hurdle has been jumped successfully. The next test will be characters and stories and I am optimistic that the new team will not produce the kind of putrid dross that made Voyager so tediously mediocre and ultimately led to Enterprise's cancellation.