I didn't say I never use it, just that it's not always the core feature. This will depend heavily on your field, but in my past work, the features that were way more essential are: scripting (+ IR lifting), xrefs, CFGs, labels/notes (in a persistent DB).
In my experience decompilers will totally ignore or fail on certain types of malicious code, so they mainly exist to assist disassembly analysis. And for that purpose, they save us an incredible amount of human hours.
For scripting, our approach is to give you access to the project file (just a YAML file), and you can make changes from any scripting language you want. Everything the user can customize is in there, all the rest is deterministically produced from that file.
I really disliked the fact that you usually need to buy into the version of Python that $TOOL requires you to use, or the fact itself that you need to use a specific language.
For xrefs, CFG and the rest: we have all of that in the UI, but we also produce them in a rich way. For instance, when we emit disassembly and decompiled code, we actually emit plain text + HTML-like markup to provide metainformation for navigation (basically, xrefs) and highlighting. So you can use all that from any language that can parse HTML/XML.
It's called PTML: https://docs.rev.ng/references/ptml/
For lifting: we use LLVM IR as our internal representation. This means that: 1) you don't have to learn an IR that no one else uses, 2) you can use off the shelf tools (e.g., KLEE for symbolic execution) but you can also use all the standard LLVM optimizations and analyses and 3) you can recompile it, but we're not into the binary translation business anymore.
Short answer: if you want to execute a program (maybe with some instrumentation, for fuzzing purposes) it's much easier to adopt a dynamic approach (i.e., emulation or virtualization). With static binary translation you can get better performance, but there's a lot of other things you need to get 100% right and that with a dynamic approach are a given (e.g., the CFG).
There's much more space of improvement in the field of analyzing code (as opposed to running it), so we're investing our energies there.
Then we're strong believers in integrating dynamic and static information, for instance see PageBuster: https://rev.ng/blog/pagebuster
But other than that, static binary translation is a feature of rev.ng in maintenance mode.
In my experience decompilers will totally ignore or fail on certain types of malicious code, so they mainly exist to assist disassembly analysis. And for that purpose, they save us an incredible amount of human hours.