> Show me any zstd level that has significantly different speed and data size than one of the levels of those three can't match.

In case you are not just trolling, I had some very large JSON file with a large amount of text in my SSD around and the compression time was as follows [1]:

    8,826,654,133       original
    4,763,212,322  0:29 lz4 -1
    3,815,508,500  0:52 brotli -1
    3,715,002,172  2:09 lz4 -3
    3,668,204,232  2:27 gzip -1
    3,159,659,113  1:59 brotli -2
    3,118,316,529 10:55 lzma -0 -T4
    3,025,746,073  1:21 zstd -3 -T1 (default)

Zstandard is not just lzma+gzip+lz4. It is better than everything you've mentioned at least for my test case. In fact I first compressed with zstd and tried to match the compression time for others, because zstd is very fast and using anything else as a reference point would have taken me much more time. It does have enough reason to claim itself to be "standard".

[1] Tested with i7-7700 3.60GHz and 48 GiB of RAM (but no algorithm tested use more than several MBs of memory anyway). I'm using a pretty fast SSD here so I/O speed is not much of concern. Also note that every algorithm except for lzma is single-threaded.

Isn't that exactly the point, and why it's so great? It's a single algorithm that's tune-able across that wide range of speed/ratio trade-offs using a single parameter. So you can just use one thing for almost every application instead of picking between three different things.

(Yes, I know that one parameter controls multiple different settings internally, so there are multiple dimensions if you're willing to dig that deep.)

Anyway, my recollection from looking at benchmarks a while ago: zstd used at similar ratios to lzma compresses in similar time but decompresses much faster, and it's also faster than gzip when set to comparable ratios to that. lz4 is still faster than the fastest zstd modes, and lzma at the most extreme settings still gets better ratios that the best zstd can do. But there's a huge wide swath in the middle where zstd beats them all, and that's quite valuable.

It's really not lzma+gzip+lz4, except by if you mean "it's an LZ-alike". It's a modern LZ with repcodes (kinda LZMA-ish, but more like LZX honestly), and it uses a novel arith coder system (Huffman/ANS) instead of a range/arith coder (LZMA) or none (LZ4)

Here are some DB dump compression tests done years ago, look at the pareto frontier and see that zstd wins between LZ4 and LZMA (xz): https://zeevt.github.io/compress_pareto.html