I don't understand why this is downvoted. The most obvious problem with the new calculator is it's slow startup, noticeable also wits SSD.

It's a "your mileage will vary" subjective judgment that isn't particularly helpful as a constructive criticism.

For what little it is worth, and it is presumably quite little as anecdata in present company, I've never noticed any performance issues with the Universal version of Calculator, and "time until first keypress recognition" feels the same to me as Windows 7's Win32 Calc.exe, with the old synchronous window message pump "wait for the hourglass to stop spinning" of a classic Win32 window replaced with a usually very quick splash screen.

It seems to me just as likely that y'all've forgotten all the time you've spent waiting for spinning hourglasses in Win32 (good old, rose tinted glasses phenomenon that) when you deride Universal app performance. Sure, there are plenty of Universal apps that could use a performance tune-up, in general, but there are just as many (or more likely plenty more) bad Win32 apps out there whose terrible performance is papered over with hourglasses and the passage of time afforded by Moore's Law.

When i type calc and hit enter, I espect that I can immediately type the number key strokes for the calc app, with no any pause between the enter and my first number keystroke.

I have a 8 core cpu, 32 gb ram, ssd. There is no any good reasoning for why I shoud wait for a calc app stratup.

no i just moved onto using other calculators instead of sticking to the slow windows one. maybe you should look beyond the windows standards for actually good software. a splash screen for a calculator is utterly insane