You reference Garmin, so let's look at that:
"cyber criminals targeted Garmin with a ransomware attack that
encrypted the company’s internal systems and shut down critical
"online services were interrupted including website functions,
customer support, customer-facing applications, and company
For large companies, we are not simply talking about end user files being encrypted, like Word and Excel files, but backup files and VM files. These are not typically backed up since they tend to be huge and a modern large company will have thousands of them, which makes it too difficult to copy and store on tape somewhere.
If all VMs are encrypted, and AD, backup systems, DNS, etc. are on those VMs, you have no means of logging in to anything to start a restore.
In addition, before files get encrypted, attackers tend to want to control the backup system in order to delete or corrupt the backup files in order to prevent their use in recovery.
In addition, in large companies, if there are off-site tape backups, they can take time to recover and the data might be old enough that there will be financial harm if they are used instead of trying to recover more recent data. Even a couple of day's worth of data can represent millions of lost revenue.
So, the question is not "how can we get a better backup?" but rather, "how can we limit how far an attacker can worm into our company and limit the blast radius?" Backups help, but they are not a total solution.