Nobody is 'keen' for Ukraine to surrender for fecks sake. If Russia had decided to launch an invasion of the USA, France, Japan or the UK (ie countries that have the capability to put up a sustained fight), nobody would be saying they should just surrender. If they had militaries equivalent to those countries, nobody would be saying it either.
Its not my place to tell Ukrainians whether they should 'surrender' or not but people are also being ridiculously hyperbolic with regards to the war sometimes and the flow of it, based partly on our own biases towards Ukraine and wanting to see them win and a general perception that Russia were going to win within a few days pre the war. Ukraine are not 'on the verge' of turning this around ffs; they have very little access to the sea, most of their southern coast is taken, Mariupol is essentially rubble and their capital is under an (ineffective) siege.
I imagine when people are talking about surrender, they're coming at it from the pov (rightly or wrongly) that Ukraine will ultimately lose anyway. In that case, is it better to 'lose' now and lose 10,000 people for instance or lose in 3 months and lose 100,000 people and have Mariupol and Kiev and Odessa bombed to rubble?
This presupposes that Ukraine will ultimately 'lose' of course, which may (hopefully not)vnot be the case.