This isn't true across the board. There are absolutely folks who have a $12k INEOS Pinarello because of status, but there is real value in more expensive bikes (more expensive than walmart).
Going from steel to aluminum is a very recognizable weight difference. Your commute just became more manageable.
A 105 groupset is way more reliable (ime) than lower grades. Your gears will shift better, not click, not skip, and not drop your chain during your commute.
A bike shop (which sells more expensive bikes than walmart) is going to fit you properly. You may get lucky with the walmart bike, but a proper fit removes knee pain, lower back pain, shoulder pain and neck pain.
If you are commuting, shopping, using your bike for real world things, the extra money is well worth it.
Note: I'm talking about a $500 -> ~$2k. Not a $5k bike for a commute. By ditching your car, you more than make up for the $1500 difference in insurance payments, car payments, gas payments, it really adds up quick.
Really? I feel like my old 8-speed Sora bike needs far fewer derailleur adjustments than my newer 11-speed 105 bike.
I guess this is because the higher-end groupsets are lighter-weight and have more gears (so, a thinner chain and finer mechanical tolerances).
Not everything you disagree with is "virtue signalling". As a bike commuter (i.e. ride for transport not pleasure) the difference between a Walmart bike and a $300 Trek is night and day. And between that and a $700 bike is still good, if you can afford it. Quality costs money.
People who want a car-alternative for necessity either buy a wal-mart bike, a cheap electric/gas moped, maybe a motorcycle, or walk.