Although the new versions of Windows Server 2016 and Windows 10 no longer install SMB1 as default, the majority of us are still using older systems, such as earlier versions of Windows 10, Windows 7 and Server 2012 R2 which still has SMB1 enabled.
Unfortunately, you may still find legacy systems in your environments that might rely on SMB1, such as legacy Windows Server 2003 or Linux systems, so this is something you shouldn’t just do on systems without validating beforehand, the downside is this is a VERY insecure protocol (as evidenced by WannaCry and other attacks which targeted that protocol) which needs to be eradicated from any use! To be clearer all you need to do is read this article from Ned Pyle from Microsoft back in 2016.
There are a lot of resources out there to disable SMB1, included is a PowerShell script I wrote back in 2017 that I used to assist with disabling SMB1 across workstations and used it to disable SMB1 as part of my Windows 10 Enterprise MDT builds.
To run it, save the script below as PS1 and open it PowerShell as Administrator (To open an elevated PowerShell prompt, in the Start Menu, type PowerShell. Windows PowerShell should appear on the top. Right-click on it and select Run as Administrator and navigate to where the PS1 has been saved and run it)
Note: Script is also hosted on my Github repository. Feel free to clone/recommend improvements or fork.