When Intel refused to make Apple's ARM processor for iPhones, TSMC was also unable to build a competitive high-end SOC. And yet 13 years later, here we are. Of course, Intel and TSMC both shop with ASML, and that's not a possibility anymore for SMIC, so it's not a quite similar comparison...
Yet I think it's important to keep some perspective: this Chinese/US spat is not a championship where a winner will be declared at the end of the summer. There's no reason to believe that 50 years from now either China or US will have collapsed. Xi Jinping dictatorial inclinations [1] are a threat of course, as he might decide to consolidate his power at the expense of China. But US recent [2] trend of politicians running on the hate of the other half of the US population is also a tremendous existential threat.
In any case, assuming that both US and China still stand 50 years from now, the only way for TSMC, Samsung or even Intel to stay ahead is, well, to stay ahead. It's a never-ending marathon, and in that regard funneling Huawei money into SMIC sounds very counter-productive.
[1] Moreso than his predecessors IMHO, with the notable exception of Mao. And indeed, Mao was very good at keeping China poor, underdeveloped and starving.
[2] Is it really recent? I'm French, during my two stays in the US (first time 3 years, second time 5 years) I felt a major polarization of the population, but it might have been there all along and I simply didn't notice.