"Keep calm and call clone" is a good strategy for getting things working. Don't prematurely optimize code until you know it's the bottleneck.
The latter is usually what people who use the quote "premature optimisation is the root of all evil" think it means. Don't just keep calm and clone, consider what you're cloning and why, and then hopefully we won't end up with even more horribly slow software.
Such a slippery slope between “consideration of performance” and optimization.
> Programmers waste enormous amounts of time thinking about, or worrying about, the speed of noncritical parts of their programs, and these attempts at efficiency actually have a strong negative impact when debugging and maintenance are considered. We should forget about small efficiencies, say about 97% of the time: premature optimization is the root of all evil. Yet we should not pass up our opportunities in that critical 3%.
Notice the aspects and the reasons for knuth's "premature optimization". Is it making the code harder to debug and read? Is it a non-critical path?
If an optimization doesn't impact readability or debugability (for example, picking a datastructure that fits the problem instead of just using a List for everything). Then you should do it.
I see the quote so often pulled by people that want to justify inserting a n^2 algorithm when a log(n) solution is either the same amount of code or 1 line extra.
There's also important context about the era knuth was programming in. Optimization in the era of knuth was targeting the hardware and tickling things like the CPU cache and memory in a very specific way. It was things like clever bit manipulation and packing to save memory. That's the context. In modern terms it'd be "don't use SIMD intrinsics until you know you need them". It wouldn't be "Don't think about algorithmic complexity" which is where I most often see that kludge deployed.
The point of these low/zero overhead languages like Rust is you're in an environment where memory management is ultra critical. The dotnet garbage collector does more than a good enough job for a weather app, likely a much better one than vibe coded .clone() Rust
Instead of oscillating between Rust and 1 GB webview apps just ... use the excellent managed language that exists on the operating system appropriate for GUI applications?
The app will be running on probably about a billion of devices, and Rust will reduce the footprint on each of those - assuming not a vibe coded clone app.
The additional effort isn't that big, and it would make the experience of maaaany users a bit better still.
Now extrapolate on all windows included apps and ui elements.
How much would that cost per license?
.clone() on the other hand is indeed an easy/quick fix for a lot of issues you'd face when learning rust.
Sadly, other things a bit less so - the story for the thin battery-less stdlib + npm-style churn encourages bloat, and the semantics are obsessed with safety at a heavy cost to productivity unless you spam clone() and reference-counting - but then your program becomes slow, kind of negating the advantages, you might as well have written it in C# or something...