I've still got an Ikea table my in-laws bought in the early 70s, it'll last another 30 years no problem. Some of it wasn't so bad.
They would certainly have to raise prices if they raised the quality, and then they lose their customers to competitors who are cheaper (and even worse quality - have you ever tried the cheap furniture from a hardware store?)
Furniture is a competitive market, and IKEA are very aggressive at undercutting their competition (they have directives to never let their competitors be cheaper) and they manage to sustain profits though their scale of operations (and some good engineering - IKEA have hollow tables filled with cardboard that's more durable than some competitors solid MDF stuff).
Basically people aren't willing to pay for quality. IKEAs trick is to be both cheap and have an acceptable level of design and quality.
On the low end, pretty much anything cheaper than IKEAs entry level is total garbage. I’m looking at you Target! That stuff is little better than a cardboard box.
On the high end, price rapidly outpaces quality. Every time I think “maybe I’ll get real furniture this time” the prices jump 10x. That’s just not worth it to me.
You can also order directly from places like etsy for other custom solid wood furniture around that price range: https://www.etsy.com/listing/268844007/mid-century-dining-ta...