I had downloaded the Love Letter Typewriter font from Chiaki Konaka's website that he uploaded probably 20 years ago in an old compressed format (available still at http://www.konaka.com/alice6/lain/resources.html)
I actually just checked back on the site and there is a "windows" (i.e. TTF) version available, and if I wasn't so stupid I would have noticed that and downloaded that instead of the "mac" version, which is really just a doubly compressed truetype font that macos knows how to use/extract.
So today I went through the trouble of extracting the .sit.hqx into a .sit then into a .TT (wtf is that), figuring out its an old "font suitcase" (which really should be in a .suit file I'm pretty sure) file that no one uses anymore because we don't need to. Then I went and tried to install various converters to no avail, I tried extracting the dfont something or other from the .TT, but even though Finder reported 61kb, any software I used it on said the file can't be empty. So I think I did something wrong or that when extracting the dfont, it would just strip the file of everything (idk)
I had seen fondu and its successor fontforge, but I didn't want to have to install xquartz to use it (even though this software is like ancient, the latest version needs you to be on >= macos 10.15, and I'm on 10.14)
Eventually I bit the bullet, went through the song and dance of installing xquartz, rebooting and then finally being able to extract a workable .ttf from my original download.
Now I know that it was all for nought, since Konaka had already uploaded the exact file I was looking for on his site already. But I'll still be keeping this little collection of the LLT font in various forms:

1. Love Letter Typewriter.TT - this is the extracted version of 
2. LoveLetterTypewriter.sit.hqx - the original file I downloaded from konaka.com
3. LoveLetterTypewriter.ttc - a TTC (TrueType Font Collection), in case you may need it for something...
4. LoveLetterTypewriter.ttf - what we've all been waiting for.

I'll keep this up in case konaka's site ever goes down or he removes those files, but after all these years, I doubt he'd do that so out of the blue.