It’s not everything, it’s just Chrome. Chrome is 1.6GB including all its dependencies. It’s going to be slow to start on any system if those dependencies aren’t preloaded.
Most Mac software I use (I don’t use Chrome) starts quickly because the dependencies (shared libraries) are already loaded. Chrome seems to have its own little universe of dependencies which aren’t shared and so have to be loaded on startup. This is the same reason Office 365 apps are so slow.
It's not just Chrome, it's everything, though apps that have a large number of dependencies (including Chrome and the myriad Electron apps most of us use these days) are for sure more noticeable.
My M4 MacBook Pro loads a wide range of apps - including many that have no Chromium code at all in them - noticeably slower than exactly the same app on a 4 year old Ryzen laptop running Linux, despite being approximately twice as fast at running single-threaded code, having a faster SSD, and maybe 5x the memory bandwidth.
Once they're loaded they're fine, so it's not a big deal for the day to day, but if you swap between systems regularly it does give macOS the impression of being slow and lumbering.
Disabling Gatekeeper helps but even then it's still slower. Is it APFS, the macOS I/O system, the dynamic linker, the virtual memory system, or something else? I dunno. One of these days it'll bother me enough to run some tests.
Somewhere around 2011 when I switched my MBP to an SSD (back when you could upgrade the drives, and memory, yourself), Chrome opened in 1-2 bounces of the dock icon instead of 12-14 second.
People used to make YouTube videos of their Mac opening 15 different programs in 4/5 seconds
Now, my Apple Silicon MacBook Air is very, very fast but at times it takes like 8-9 seconds to open a browser again.
I loved the MBP’s from that era. That was my first (easy) upgrade as well in addition to more memory. Those 5400 RPM hard drives were horrible. Also another slick upgrade you could do back then is to swap out the super drive with a caddy to have a second SSD/HDD.
It still works fine today, though I had install Linux on it to keep it up to date.
I'm running the latest MacOS right now on a modest m4 Mini and it doesn't seem slow to me at all. I use Windows for gaming and Linux for several of my machines as well and I don't "feel" like MacOS is slow.
In any case, Chrome opens quickly on my Mac Mini, under a second when I launch it from clicking its icon in my task bar or from spotlight (which is my normal way of starting apps). When Chrome is idle with no windows, opening chrome seems even faster, almost instant.
This made me curious so I tried opening some Apple apps, and they appear to open about the same speed as Chrome.
Gui applications like Chrome or Keynote can be opened from a terminal command line using the open command so I tried timing this:
$ time open /Applications/Google\ Chrome.app
which indicated that open was finished in under 0.05 seconds total. So this wasn't useful because it appears to be timing only part of the time involved with getting the first window up.
It's always been that way. Even when I had a maxed out current-gen Mac Pro in 2008, it still launched and ran faster in Windows than MacOS.
I have seen people suggesting that it's because of app signature checks choking on Internet slowness, but 1. those are cached, so the second run should be faster, and in non-networked instances the speed is unchanged, and 2. I don't believe those were even implemented back in 2002 when I got my iMac G4, and it was likewise far quicker in Linux than in OS X.
At the time (2002), I joked that it was because the computer was running two operating systems at once: NeXTSTEP and FreeBSD.
Why is eveything so slow on new MacOS?