No, it's not.
I regularly make good, usable prints from images made at ISO 3200, 5000 and 6400 with my pair of 7DII. On rarer occasions, even higher...
Canon 7DII test shot at ISO 16000....
Above was shot RAW and post-processed into JPEG through Lightroom 6 with minimal cropping, slight boost in contrast, and only the software's default levels of noise reduction and sharpening applied. I took a lot of care to avoid any under-exposure... no increase in image brightness was needed.
With any digital camera, to minimize noise issues I think the keys are:
1. Avoid underexposure.... if you have to boost exposure in post-processing, it will greatly amplify noise. ETTR is one technique used to help avoid underexposure.
2. Fill your viewfinder with your subject.... minimize cropping. Above image detail on the right is probably close to "100%", and noise begins to show. It will with any camera (though it's pretty well controlled in the above example).
3. Use proper work flow.... noise reduction should be applied early in the process, before resizing the image... and especially before sharpening, which should be one of the very last steps (well after any re-sizing is done). Also take care not to over-sharpen, because that will also amplify the appearance of noise.
4. Be realistic.... Looking at a 7DII's image "at 100%" on your computer monitor is like making a three by five foot wide print, then viewing it from 18 or 20" away! Of course it looks like crap! (Same effect as over-cropping an image.) Sure, it's fine to zoom in to high magnifications for retouching work.... But, when evaluating images for noise, focus accuracy, sharpness, etc., back off to a more reasonable and sensible magnification. View the image at a size close to your intended use of the image (even then, a computer monitor rendition is nowhere near as sharp and fine as a quality print will be... even the best monitors also clip the dynamic range of images, too. I.e., there's more detail in shadows and highlights of a quality print, than you'll see on-screen.)
5. For super high ISOs, it may help to use additional noise reduction... I use a Noiseware plug-in with Photoshop (also available as a stand-alone software, if not a Photoshop user). But I think even Lightroom 6 does a pretty good job.
I shoot a lot of action, rarely use my 7DIIs below ISO 400, use them freely up to ISO 3200 and occasionally even higher than that with added post-processing noise reduction, when necessary.
No, it's not. br br I regularly make good, usable... (