I think it's unreasonable for any app to be so slow to launch that this matters. Modern SSDs have 7000MB/s or more read speeds. Assuming a ridiculously bloated app of 100MB, that's enough to load the whole thing into RAM in less than a frame at the most common monitor refresh rate. The only explanation for slow load times on modern hardware is bad software.
I think it's unreasonable for any app to be so slow to launch that this matters.
That doesn't change the fact that very many apps are in fact that slow that it does matter.
I'm on an HDD and Signal Desktop is 400+ MB, so
The network is always down, the disk is always slow, and the OS never schedules your threads. Keep those in mind and your code might be good