It would be easier to not attack a strawman, if the "anti-austeritists" told us what their alternatives are. It's hard to have a debat with people who have decided their opposition is evil and you don't know what they're thinking as a alternative. What can Greece do instead of austerity, if they also want to stay in the Euro? If the other side doesn't have a coherent alternative, they choose to be strawmen.
The obsessive harping about whether its "realistic" to stay in the Euro while fulfilling various demands of the government is a straw man, because its not an outcome that either Tsipras or the average Greek expects.
Disregarding whether its "practical" or whatever, by saying Greece wants to stay in the Euro Tsipras is making an important distinction. He is making the distinction that he supports the Euro if not for xyz issues where public opinion if overwhelmingly on the Government's side. This may not be different in practice from turning around and marching out of negotiations saying that Greece is better off with the drachma, but he is making the distinction for political purposes, namely so he can very clearly demonstrate the reasons Greece is being forced out/choosing to leave the Euro (again, xyz issues where public opinion is overwhelmingly on the Governments side) which may very well be terms on which the Greek peoples can accept leaving the Euro.
He has his opinions and he is
marketing them, something which (for better or worse) is alien to the sociopathic opposition which is
also taking an unpopular position in many ways, but which outright refuses to participate in any debate or defend any of their ideas, and whose position more or less boils down to "do what we say or we will make you suffer in ways that we won't exactly sketch out."
The distinction he is making may not matter or make sense to you, but he isn't doing it for you. He is making that distinction because the Greek people by and large want that distinction to be made, and that's why he keeps winning his political battles and why SYRIZA is sky high in the polls. Because Tsipras and SYRIZA are the ones at least paying lip service to what the Greek people want, and its always been my suspicion that that's really all voters anywhere really want. His (relevant) critics on the other hand
seemingly take outright pleasure in mooning the public and totally disregarding public opinion.
Note that this is overall not a note about who is "right" and who is "wrong" but a political point, and one that certain Tsipras critics would be well to heed because the tsundere strategy of saying "we don't care if Greece leaves, no, really" is obviously bankrupt.