I got ill in late March. It's now June, and I'm still not well. I'm a lot better than I was, and I can have very good days, and then something will happen (my blood pressure will plummet suddenly, or I will get breathing problems again, or I will have vomiting and a bad stomach, or I will just be so tired it exhausts me to sit on the sofa) and then I'm back in bed again. There's been times during the course of this illness my teenage DS has had to come and check on me every 15 minutes or so, just in case I get worse, and there's been times I have been afraid to go to sleep at night in case he finds my corpse in the morning. (I believe I'm past that point, but there's been so many weird things about this disease that it's hard to relax.)
I'm a "mild" case, and there's plenty like me. I have had a couple of weeks of beginning to work again, to go out (I'm no longer infectious) but I've basically spent most of lockdown bedbound, doing fuck all, alternating between sleep and terror.
Long story short: yes, for many people, even ones who mostly rode it out at home, it can be very bad.
If you get it, you probably won't die. That's what kept the worst of the fear away. You probably won't die. You might be completely asymptomatic, and have no problems at all. You might have a bad cold for a week and then be fine. Or - even if you remain a "mild" case - you might end up like me. It's something of a lottery.