Opinion of Alexis Tsipras

[Bacon King]

Mega-HP. He is a weak leader that can't control even his own party.
He has appointed a psychopathic narcissist  as FinMin, a crypto-fascist shrew as President of the Parliament and a bunch of incompetent anti-European neo-Stalinists and far-right loons at his cabinet.

His indecisiveness and procrastination has brought us into a much worse place than we were four months ago, his arrogance and divisive rhetoric has alienated even our closest allies (Cyprus) and his only "accomplishments" so far have been the abolishment of the few structural reforms enacted by the previous governments. 

At least from the polls, it seems that the Greek people support him, which should count for something.

Not anymore. Approval of his government has fallen from 83% in February to 40% now.

What was Samaras's approval this many months in?

Samaras's approval was consistently low. He was always seen as the lesser of two evils.
Tsipras OTOH was elected with great hopes of bringing something new but he quickly showed his true colors of being just another politician hellbent to protect and strengthen the clientelistic state that brought the crisis.

genuine question- with Tsipras's fall in popularity, why is SYRIZA still polling double-digit leads?

[Bacon King]

Huh? Where do they get these data?
Just yesterday we had a new poll where SYRIZA's lead declined from 14,5 points to 12. And that was one of the best for them in a long time.

The big seems to be a lack of quality control and the simple fact that there's bound to be more bad polls than good. Wikipedia shows this poll with a 29 point SYRIZA lead; it was conducted on behalf of a leftist pro-SYRIZA radio station in Athens, 105.5 The Reds and appears to be ideologically motivated. Another common sight (and terrible methodological practice) is that many polls like this SYRIZA +26 poll ask the headline voting question at the very end of the poll, rather than leading with it.

A second issue is that for polls with undecideds, Wikipedia allocates the undecideds proportionally among all the parties. This is done to keep those polls consistent/comparable with the pollsters that allocate undecided pollsters themselves before publishing the data, but has a side-effect of slightly exaggerating the lead of the party in first place (for example, this poll has a 9.1 point SYRIZA lead but wikipedia ends up with a 10.4 point SYRIZA lead). The bigger the lead is, the more it increases after the adjustment.

[Bacon King]

There's no happy ending to this story is there? Depressing.

Greece is near bottom and will soon start to recover, no matter how badly they screw up. If they're ejected from the euro, they will suddenly hit bottom and have nowhere to go but up. If they capitulate, they will resume the upward trend they were on before Tsipiras.

In either case it might be slightly relevant to note that literal neo-nazis polled third place in the last election and still exist as a thing