There certainly is more to 'Apple did it first' than hype. Those who claim Apple did it first often do so out of ignorance rather than hype. They simply assume that Apple is the leading innovator which is copied by others.
On you questions about other phones showing live preview or looking 'as good' (something which surely is subjective?) I can only advice you to look at test reports for mobile devices in the last few years. In most cases Samsung seems to top the list, both in the photo quality department as well as the (subjective) 'looks' category. A quick search for 'best camera phone' for the last two years and a tally of the results shows the Samsung Galaxy S7 (Edge or normal) to win in 2016, the Samsung Galaxy S6 and LG G4 in 2015. Apple does compete in this market and ends up performing above average but others do better.
So, to return to your statement about is being 'wise to consider that there might be more to "Apple did it first" than hype, specially since it's such a common praise/criticism'; yes, there is more to it, but it is not founded on the fact that Apple always make superior products. They make products of above average quality and sell them at an above average price to a captive audience which is convinced of the superiority of their choice above others. That conviction is not based on direct comparison with other products, it merely stems from their conviction of Apple being 'first' and 'best'. The captive audience is kept that way by the closed nature of Apple's product lines - hardware and software alike - which often makes it more expensive to 'switch sides' than to plunk down for the next iteration of iSomething or Macsomething