I understand the LIRR is in a hole. I also understand that it wants to reduce costs and that the LIRR service to Greenport is expensive to run. Nonetheless, there are drawbacks to summer-weekend-only operation, including partial line abandonment and the resulting repair costs for track, resulting slower trains on summer weekends, less overall transit service to and from the East End, a for-profit transit monopoly (Hampton Jitney) between the city and the East End (Long Islanders ought to look up the complaints the Victorians made against their railroad monopolies!), lack of interisland transit access (Suffolk Transit's bus service only appears marginally acceptable), etc. Also, a service elimination might be hard to reverse. I wonder how East Enders feel about it, but Newsday stuck it to me by requiring people to have a subscription to read their stories. That does not suit a very occasional reader like me.

I'm unfamiliar with Long Island. What is Greenport like?

Greenport is a small, diverse, village within the town of Southold. Population is 2,048. Greenport is as far east as you can go in Suffolk County.

The Main Line uses diesels for the service to Ronkonkama.

I think that if there are going to be a lot of communities affected, they should run bus service from the Ronkonkoma station (I think that's where the Greenport line starts) to points further east, and have the main line train connect to the bus. They could charge the same current fares as the train, without all the expenses of running the train (like having to run the engines for a long time, wasting the fuel, like the story in Long Island City). This could help if they feel the ridership is really that low.

Checkmate: An interesting idea-bring back the North Fork "Road and Rail" service discontinued in the early 80s-but I would rather see more service between Ronkonkoma and Greenport even if a East End transit authority ran the line.
Running this line only on summer weekends between those points would fall way short of what East End residents would want with what they pay in MTA taxes.

EE: Greenport is basically a New England-style fishing village - 94 miles E on the Main Line. It is about 9 miles E to Orient and the New London ferry terminal-the S92 SCT bus serves it from Greenport Village. Montauk Point on the South Fork is about
124 miles from Manhattan and about 5 miles from the Montauk LIRR station-that is truly "THE END"(as they promote themselves)as far as Long Island is concerned.

MACTRAXX

The sad thing is that plenty of people head to Riverhead for the Tanger Outlet. However, LIRR service is so anemic that they use the Hampton Jitney.

There was an article that residents wanted the early train to run earlier but MTA refused. SErvice is very limited there and residents should have a voice in timetables.

I agree that it would be better to have the MTA run a whole train as opposed to a bus, but hey, a bus is better than no service at all. At least it would reduce the dependance on Hampton Jitney.
Some of the cuts need to at least be replaced by bus service. For example, the late night cuts to Atlantic Terminal could be replaced by a bus from Jamaica. 430 weekday and 720 weekend passangers would, according to them have to take a train to Penn Station and transfer to the subway, making for a long and circuituous route. In theory, riders could also take the J to Broadway Junction and then take the A, but that is a long trip, not to mention that it is more expensive to go into Manhattan and then take a subway than it is to go to Brooklyn.
There are 3 lines terminating in Jamaica, so the LIRR can combine trips like the 2:18 AM and 2:32AM weekday trips from Jamaica, and put them on one bus. The buses would get riders. There are about 10 late night trips with 430 weekday and 720 weekend riders. The westbound weekday trips would get about 13 riders per bus, and the eastbound trips would get 30 riders (average) (according to the stats). The weekend trips would get an average of 26 westbound and 46 eastbound riders per bus.
I think those numbers justify running a bus.

But if service is cut on the Greenport line, doesn't the LIRR lose access to the entire Ronkonkoma line which is a stipulation to a contract from the 19th Century as per NYCTF.