I'm still using Picasa every day (the Windows program), not the Picasa Web Albums. I will cling to it until it is no longer functional or something comparable comes along. I've seen nothing else that even comes close to meeting my photo needs. There are still throngs of people complaining online daily about Google dumping it.
Can't download it directly from Google anymore, but others have made it available.
I use it extensively for captions, keyword and gps tags, facial recognition and face tags, and then sorting, searching, and creating with that data. I also use it for basic edits, touch-ups, crops, adjustments, exporting copies, or e-mailing them. It still
works for simply uploading pictures and albums to Google Photos for backing them up and sharing with others. The sync functions still kind of work, but can be problematic at times. I can use Picasa Starter to make custom buttons in the program that run scripts through EXIFtool for more advanced functions. Google abandoned the Picasa program telling everyone to just use Google Photos (the website and app) for everything, and to do everything in the cloud. That's like telling people they could just replace their car with a skateboard.
Also another thumbs up for IrfanView. I have used that a lot for batch processing photos. It is a very powerful yet quick program for edits and viewing. Not quite as simple as Picasa though. Many use Gimp too, it's like the freeware version of Photoshop. I never took the time learn it and just occasionally use my VERY old Corel Photo-Paint for some "photoshop" type things since I already know how to use it. I have also heard good things about FastStone Image Viewer, but haven't tried it out yet myself.
When I "upgraded"
from Windows 7 to Windows 10, I immediately went in and disabled all of its attempts to manage my pictures. I hate that stuff. When it does the forced Windows updates though I've found it often sneakily adds in more automatic "helpful" things that I don't want it messing with. I've been eying Linux Mint as a possible future alternative lately to Windows. What Linux did you go with
@RoseBlush1?