From my observations:
It appears less to me a western/ NATO/ US "strategy" along these lines... and more a specific Ukrainian policy to not incur drastic casualties in this offensive. I don't disagree that Ukraine would need more offensive equipment to ensure a successful offensive... but I think it also requires additional manpower/ and additional casualties to conduct such an operation.
I saw an interesting hypothesis: That with a Ukrainian insurgency behind the lines, and the HIMARS at the front lines (and out of Russia's range as long as they can avoid Russian air power; which is retreating back into Russia anyways after successful attacks in Crimea against them...); that Ukraine can absolutely bleed Russia nearly to death and, instead of engaging in all all-out assault to take Kherson, for example (weakening troop strength holding the line in Donetsk Oblast), instead... they can have smaller, more mobile units hit and strike Russian forces in multiple attacks. Without an all out assault, and without intense casualties that that would entail.
PS: And not strengthening one area at the expense of weakening several others... (that's the problem of protecting or taking back Ukrainian territory... wide dispersal of troops across multiple fronts...).
I'm not certain they are banking on it but:
Putin is banking that he can short-shift gas to Germany/ Europe to the point they become desperate this winter and "force" Ukraine to capitulate to Putin's terms. That's what Russia is banking on...
Ukraine? I don't know... Is Zelensky serious he thinks he can retake Crimea or is he just trying to get Putin to taste the battery acid that's in his mouth? Ukraine is going to have to take something... this stalemate will allow Putin to put the pressure on Europe, without any reward of Ukraine taking back any land. That's not winning formula. I know they want to avoid casualties... but without any retaking of Ukrainian territory... the rest of the world, aside from the US, will get discouraged, at the very least. I've been pressing for Ukraine to take back Kherson for... 2 months now?
C'mon Zelensky... gotta figure this out and not just talk about it!!!
(I think he's been talking in order to convince Russia to pull troops out of Donetsk and put them in Kherson... Check. And then they took out the bridges to trap those troops on the wrong side of the Dnieper... Check. And their secret ops took out multiple Crimean targets to get Russia to pull back their supply/ defensive forces out of Crimea that would support a Kherson defense against a Ukrainian attack to recover Kherson... Check. But... NOW's the time guys!!!)