I’ll quote myself on this: Time indicators - I'm struggling - #11 by Jonapedia
It’s quite a long post that runs through an entire list of words like the ones you mentioned, so take your time. I cover 近日 and 近年 right at the end. 年来 gets covered a bit higher up. The short version though:
- 近日 can actually refer to both the past and the future. The future version is more common, but it’s not wrong to use it to refer to the past either. The reason the usage that refers to the past is less common is probably due to overlap with words like 先日, which you mentioned.
- 近年 most likely doesn’t get used to refer to the future because it’s hard to project yourself several years into the future. That’s my opinion.
Basically, however, the 近〜 phrases you’ve mentioned probably had their meanings determined by usage.
- 年来: I’ve said this before, and I’ll say it again – ‘What comes before modifies what comes after.’ It’s a near-universal rule in Japanese and Chinese, especially when kanji are involved. 来年 and all the other 来〜 phrases have 来 come first, so they definitely mean ‘coming 〜’. The noun gets modified by 来. When you change the order, it’s 来 that gets modified by 年. I know I said something slightly different in the post I linked to above, but now that I think about the 〜来 phrases I know in Chinese (because that’s where this expression comes from, I’m pretty sure: we use 年来 in Mandarin as well (yes, I’m a Chinese speaker))… basically, 来 is a verb or an indicator of the direction of movement (specifically ‘towards the speaker’), and 年 is an adverb indicating duration. Think of Japanese phrases like 十年勉強してきた (‘I’ve been studying for ten years’): that きた is a form of 来る! Years have passed, and the time has come. It’s been ‘years coming’, as I said in the other post.
I hope all that makes more sense now. All the best!