I've never seen JPEG artifacts on images modified/saved 5 or fewer times. Viewing on a monitor including at 100%, printing photos, whatever - in practice the artifacts don't matter.
jpeg artifacts mainly show up on drawings. where they seriously degrade masking operations. which is a hobby of mine. so I always appreciate it when a drawing is a png. rather than a bunch of jpeg goop.
JPEG artifacts are less disturbing because they're so obviously artificial. WEBP and similar artifacts look more natural, which makes them harder to ignore.
For non-photographic images, I'm horribly sensible to the ringing artifacts. Thankfully, there's waifu2x (in denoise mode only) to remove those when textures don't confuse it too much and I use MozJPEG to encode, which really improves the result.
There's something to be said about this. A high quality JPEG after cleanup can sometimes be larger than an ARW (sony RAW) on export and it makes no sense to me.
Well, as JPEGs? Why not? Quality is just fine if you don't touch the quality slider in Photoshop or other software.
For "more" there's still lossless camera RAW formats and large image formats like PSD and whatnot.
JPEG is just fine.