Generally 'survival' is uncountable shows that you realise that it is in general unhelpful and unwise to class nouns as count[able] or non-count[able]. It is usages that must be analysed; many nouns display both count and non-count behaviour. Thus 'coffee' is non-count in 'Coffee is my favourite drink' but count in 'The two main coffees are robusta and arabica' and 'Four coffees, please.'
Wiktionary gives the plural [form at least] survivals. And below, a reasonable example of a usage:
- Cultural Survivals Theory and Traditional Customs: An Examination of the Effects of Privileging on the Form and Perception of Some
English Calendar Customs
[Georgina Boyes; Journal of Ethnological Studies_Taylor Francis Online]
So we should perhaps expect 'struggle is countable' to be an over-simplification.
Checking on the internet gives a lot of examples of obvious count usages (for example, 'Hitler's three struggles', 'Today, we will look at six struggles that WordPress entrepreneurs overcome to be successful'). But such example sentences seem rare in dictionaries. And indeed, Collins CoBuild classes struggle as count/non-count ('variable' in their terms), and even 'mandatorily single' in one usage:
- VARIABLE NOUN [NOUN to-infinitive] A struggle is a long and difficult attempt to achieve something such as freedom or political
- Life became a struggle for survival. [+ for]
- ...a young lad's struggle to support his poverty-stricken family.
- He is currently locked in a power struggle with his Prime Minister. [+ with] ...
- SINGULAR NOUN An action or activity that is a struggle is very difficult to do.
- Losing weight was a terrible struggle.
Certainly the example in the last example cannot be considered count ('losing six weights'?), but I feel it must be classed as non-count rather than singular (though obviously it's singular in form). But I'd say all the other examples resist (at least) the addition of a numeral. Classification as to count/non-count is murky here. And with
- I find the children a struggle.
I'd say this is cast-iron non-count.
Non-count usages do indeed often refer to generalities and/or states. The particular is emphasised by a singular count usage, so there is obviously more focus (I wouldn't say less vagueness).
'Beer is found almost in every civilisation.' 'This beer (These three beers) is/are worth travelling all the way to Hartlepool for.'
Wood is a very useful material to build with.' '[One wood]/Two woods I really love working with are maple and walnut.'
'Sin is evil.' 'One sin (/Two sins) I really struggle to overcome is/are ....'
So I'd say Collins seems to give the most detailed analysis, but doesn't label specific examples (unless 'variable' is used to mean 'intermediate'!) The test for countness is whether a numeral may be used with a noun. Even here, there are disputable cases.