Only a few short years ago I would shutter (pun intended) at the thought of capturing an image above ISO 800. I would not want to deal with the noise and loss of image detail. With my Canon 5D Mark IV that fear is gone. The image below was taken with my 5D Mark IV and a 24-70 f2.8 Canon lens. The camera settings were: ISO 10,000 f2.8 1/250sec. The shot was taken indoors with some soft side light.

Once the image was imported into Lightroom I was very impressed with the low noise level.
I made a few LR adjustments and set the noise reduction slider to 25.
Making this image very usable for print or web. I will definitely be using the higher ISO setting when needed without the fear of getting an unusable image.