Given that LTT has over 15 million subs and between 1 and 2 million views on every single video - yes, there is a very high chance that some of these people (maybe hundreds, in fact) did base their purchasing choices on LTT videos which had horrible mistakes.
And yes, Linus is not their financial or technical or whatever other advisor so he's not legally liable for their purchasing decisions. However, like with printed media, if you consistently give the audience the wrong advice, you eventually lose your reputation.