How to fix drag and drop issue resulting in hanging finder that occurs on all Macs purchased in last 2 or 3 years?

I have been using many Macs, including ones currently on Catalina, Big Sur, Monterey, and Ventura. Never seen the hesitation you describe. That makes me wonder if somehow you have installed something that is responsible for this. You say it happens "right out of the box," but have you migrated your files and accounts and setup? If you go to an Apple Store, where dozens of Macs are set up and running on display, none of them show such hesitation. To figure this out, download Etrecheck (free) and run it, post the output here using the "Additional text" button below. People reading here will review it to see if it offers some clues. Etrecheck output contains only anonymous information about what is installed and your Mac's configuration. You can check it before posting it. Etrecheck is also open source software.

Creating a new user account and checking if the issue persists can help determine whether the problem is specific to your user account or system-wide. Additionally, try booting your Mac in Safe Mode (by holding the "Shift" key during startup) to check for third-party software conflicts. If you recently installed any new applications, consider uninstalling them to see if they are causing the drag and drop problem.

In case the issue still persists, try resetting the NVRAM (on Intel-based Macs) or PRAM (on older Macs) by holding down "Option + Command + P + R" during startup until you hear the startup sound for the second time. If none of the above steps work, consider backing up your data and performing a clean installation of macOS......

A simple restart can often resolve temporary software glitches and improve system performance. Check for macOS updates: Make sure your Mac is running the latest version of macOS. Apple regularly releases updates that address bugs and improve system stability. Go to the Apple menu > System Preferences > Software Update to check for and install any available updates. Sometimes, issues with Finder can be resolved by resetting its preferences. Open Finder and click on the "Finder" menu at the top of the screen. Select "Preferences" and then click on the "Advanced" tab. Click the "Reset…" button to reset Finder preferences to their default settings. Finder's cache files can sometimes cause issues. To clear the cache, open a Finder window and press Command + Shift + G. In the "Go to the folder" dialog box, enter "~/Library/Caches" (without quotes) and press Enter. Locate the "com.apple.finder" folder and delete it. Empty the Trash and restart your Mac.

If you are experiencing a drag and drop issue on your Mac purchased within the last 2 or 3 years, there are several troubleshooting steps you can try to resolve the problem. First, start by restarting your Mac, as sometimes a simple reboot can fix temporary software glitches. Check for macOS updates to ensure your system is running the latest version, as Apple regularly releases updates with bug fixes and improvements. Additionally, verify if there are any updates available for the specific app in which the drag and drop problem occurs.

Resetting Finder preferences to default settings can help, and you can do this by going to "Finder" > "Preferences" > "Advanced" and clicking "Reset Warnings" and "Reset All Finder Windows." Running Disk Utility can help identify and repair any disk-related issues, and you can access it through "Applications" > "Utilities" > "Disk Utility."

Are you running any anti-virus apps, cleaning/optimizer apps, or third party security software?

Try booting into Safe Mode to see if the same thing occurs.

Does it happen with every folder or only certain folders?

Which view are you using in the Finder?

Edit: What type of drive does your iMac use? Hard Drive, SSD, or Fusion Drive?

I think you're going to need to provide more details.

I can't say I've experienced this, which means there has to be something specific to either the files in question, or how you're moving them.

Never seen this and we have 5 Macs now (2015-2020); one older one has been retired

We've had six Macs in the last eight years; five now since we traded one in.

We've never experienced your issue on any one of them and two of them operated on Big Sur until Monterey came along.