As for learning to distinguish X from Sh, and the Ch/J/Zh/Q and C/Z distinctions in Mandarin, I think your beliefs may have swung too far from one pole to the other. It took me six or seven years to learn to pronounce American English [ɹ] correctly, and I made lots of hearing errors during that time as well. It can take time to learn to hear phonetic differences. Unsurprisingly you weren't able to learn the difference between [ɕ] and [ʂ] in a single fifteen-minute session, but if you'd done two fifteen-minute sessions a day for two years, you'd almost certainly get it. In fact, you might find that it only takes you a few weeks!
You're right though. I could probably get Chinese pronunciation correct given enough time and effort. but it's not trivial, like I thought earlier.
(non-Tamil here) Off the top of my head I can think of at least two distinct ways I have heard native Tamils speakers pronounce the name, and both are convinced that they are correct. Plenty of Tamils pronounce it with a retroflex 'r', while a majority consider it archaic and pronounce it with a retroflex 'l'.
The ழ was originally kind of a retroflex 'r' sound, but many Tamils consider it archaic & pronounce it as similar to a retroflex 'l' ள் - when questioned a native Tamil speaker from Tamil Nadu told me that ள் and ழ are pronounced the same.
Consider the word வாழை பழம் (banana), with two retroflex 'r' sounds. I have heard people pronounce it with both (and how its retained in Malayalam), and many will change one of them to a retroflex 'l'. In my restricted sample of asking a handful of native speakers to say the word, at least one consistently changed both to a retroflex 'l'.
So when I'm with non-Cantonese speaking people, I go by a random Anglo name I picked for myself decades ago. Honestly, I feel more attached to that name than any non-Cantonese pronunciation of my legal name.
It gets annoying when some well meaning people insist that they must learn how to pronounce my "real name", it leaves me two choices:
A) Lie and say that their attempt is good, and resign to never knowing if they're calling me for the rest of time, or
B) Repeat it dozens of time until they give up, and sometimes have them complain that they never encountered those sounds in their Chinese 101 class...
So while I think it's good to make an effort to pronounce names correctly, it's probably better to give up after a few honest attempt, if the person you are addressing don't mind.
Sort of. I’d speculate that those who care about it the most are people who’ve never struggled and failed to pronounce a name in another language. In my limited experience of knowing 3 languages I never had trouble with any pronunciation. So I came to the unfounded conclusion that a. I can pronounce anything and b. everyone should pronounce everything correctly and if they don’t, it’s for lack of effort.
I was wrong. I learned this while learning how to pronounce Chinese names. I thought I was saying them right. For example I’d pronounce “Xi” as “Shi”. But it wasn’t the right Shi, evidently (https://en.m.wikipedia.org/wiki/Lion-Eating_Poet_in_the_Ston...). My friend sat with me patiently as I attempted it over and over. Every time she’d say “no, not Shi, it’s more like Shi”. I couldn’t hear the difference. So even if I put in more time, I wouldn’t succeed.
So now I’m more tolerant of people making mistakes. As long as they make an effort, it’s good enough.
If anyone would like a challenge, try pronouncing the word “Tamil” from the language Tamil. I haven’t heard anyone who wasn’t a native speaker pronounce it correctly.