Is heel and toe a deal killer on a street car?

I say yes.  The V6 MG is a blast but something more current with a roof and a stick would be a better choice for me.  Drove a 2021 Corolla SE 6 speed, had many nice things but durn it I can't heel and toe downshifts because the pedals are wrong.  My ankle will just barely flex to do it instead of a nice comfortable motion.  I know I don't need to but it is fun.  So is shifting without the clutch once in a while but wasn't bringing that up on a test drive.  

So how many of you out there know how and have a decent econobox that allows it?  Keep going back the the Civic SI, might be the best choice.

It's the norm to have to fit oversized pedals to enable heel-and-toe downshifts, especially on non-sporty cars or even lower-end sports cars, so don't think of it as an immutable feature of a car. I've made changes to the pedals on my AE92 and Toyobaru for this reason. The Samurai's pedal spacing was hopeless so I use a reverse heel-toe technique with that.

I'd imagine that cars like the Corolla and Civic Si would have enough of an aftermarket that there's a solution there.

If you're going used, I'd also add in two cars from Hyundai:

• Elantra Sport: I don't remember the exact year range (2019-ish, I think), but the could be had with a 6-speed manual. On paper, it was comparative to the Civic Si
• Elantra GT N-Line: Similar experience, but in hatchback form. I drove one equipped with the DCT a few years and had a blast. I can only imagine the manual makes it more fun.

I've been able to do it decently in every car I've driven with the exception of a 2000ish Tacoma (and an air cooled 911 with the seat positioned for someone 6" shorter than me). Modern cars tend to have softer brake pedals with longer pedal travel. If you're braking hard, the pedals will probably line up pretty well; if you're rolling up to a stop with basically no pedal pressure, probably not so much. Start working on that ankle mobility I guess.

Maybe because I taught myself to heel/toe wrong, but I've never met a car I can't do it in. I heel/toe my XJ even

Most oem TBW tuning is too slow for satisfying heel toe use anyways.

I don't think there's a right or wrong way to do it, generally. Just do what works. I also find it easier when the brake pedal is resting squarely on (or near) the floor and I can just rotate my foot over to the accelerator pedal nearby.

Edit: To answer the OP's question, no, I don't think it's a deal killer. If I like the car enough, I'll figure out something to make it work.

I have bent the throttle pedal on nearly every car I have owned. just be careful to not break any plastic brackets if bending a metal pedal. Plastic pedal needs an added on piece, all doable.

i have never learned how to heal toe appropriately and rarely find my ability to drive stick on the street lacking.  On track it sucks because I have to slip the clutch out slower when downshifting (I purchased a autoblip to help /w this for next season) but on the street, if I need to downshift its generally to accelerate so I can just blip the throttle with my foot on downshift and on braking, i rarely need the mechanical advantage of a lower gear.  

I figure out whatever motion is needed for heel toe. I have big feet and flexible ankles so that probably helps.