I don't know if this has been covered on this forum yet. I am a member of a few other photography forums and one of them talks about the death of the 7D and 5D series cameras. They are being replaced with the mirrorless cameras. I really like my 7D & 5D cameras. What a shame they are being discontinued.
I really like my 6D Mark II and was going to get the 7D Mark III but it will never be built. I got the R6 and honestly, once you shoot one of these, you will be converted. The list of reasons why is very long. Now, I'm waiting for the R7 and will get on the list for that, hopefully for delivery this summer. You'll get great results from your 5D and 7D for years to come. Nothing can replace the skills you have developed using them, But some of the capabilities of the new mirrorless cameras will amplify those skills.
Well being a bit on the quirky side, I spent around $600 this past three weeks on a $95 D90, a $30 D1x, a $65 85mm, a $80 35-135, a $125 70-210 and a $250 80-400 VR. IMO, its the photographer, not the equipment.
Doesn't mean that you should stop using them. Mirrorless have their faults. Since it has EVF, its likely to drain power more quickly than OVF And they're not cheap either, even more expensive than two 5D mkiii
Also, you really shouldn't be upgrading to a new model just because they've release one (or maybe slightly more than one) every year, it should only because you need to get a new model
I think if you want something and can afford it, why not get it? Life's too short not to have it's little pleasures. The doctrine that you need to 'need' something before you get it is nonsensical imo. For me anyhow.
I was NOT going to go mirrorless just for the sake of getting the shiny new thing. I got it because it enabled me to get the most out of my investment in L series glass. Example: I just came inside from taking shots of birds: Chickadees. I have the 100-400 L Mark II and the 1.4 and 2.0 teleconverters. The 2.0 TC on that lens is F 11. My 6D can only focus at that F stop in live view. Not very good for action shots. The R6 not only does it with ease, it has eye tracking and in body stabilization. AND, the low light performance is such that I've taken shots at 16000 and 20000 (I was in auto ISO at the time so I didn't know until later what the camera actually used) and was shocked when later I saw the ISO setting. The shots were remarkably clean. So I will keep the 6D Mark II and continue to get great use from in many situations. But there are other situations, that I shoot regularly, where the R6 is simply a better tool. The decision is unique to each person's requirements.
I don't know if that is so unusual. I still wish I had the 1965 VW Bug my folks let me drive in High School. No bells, Not whistles. No FM. But, loads of fun to drive.