A feature of modern computing is the use of very low power systems (I programme mostly for Raspberry PI - not very low power) and/or systems run on "pay as you go" platforms which can scale hugely.

Rust is very efficient at run time. (Not at programming time nor compile time) so is very useful in these cases.

A counter example, from my life, to illustrate: I ran a mail server for a group I was involved with. I spun up a VPS and Mailman. (Mailman v3 is built on Django/Python). I had to double the capacity of the VPS as 500MB of memory was not enough to install and run Mailman (I think the problem was at install time, but that made very little difference). The cost of my mail server doubled because of the inefficiency of the Django/Python framework.

Django is very efficient at programming time, but is resource hungry. The original Mailman ran in 40k, the "modern" version was not usable on a platform with 500MB.

For me it was no biggy. One server, $10 not $5 a month. Mēh! But if that were a million instances.....

So with all the progress in computers getting more powerful the actual instances we use are getting weaker (for very good reasons). A language like Rust can be very helpful in this case.

(On the Raspberry Pi I use Rust for realtime control of audio processes)