If all things were equal and the proper amount of money was invested into said NVR / DVR. That appliance would last easily ten years.
With the advent of incorporating POE into the same NVR chassis at a low price point. It’s pretty rare to see one last ten years much less five.
The vast majority of the people on this forum and thousands like it. Purchase based on low price while trying to balance overall value & reliability.
The Chinese have done an incredible feat in providing billions of random hardware that meets almost any price point while making profit!
When you have such a mentality and low budget for something that’s so important. You simply can’t expect X vs Y to offer the same level of durability and performance at such low prices.
The market certainly has those diamonds in the rough that we all know and use. But, that same market offers more junk that literally is a ticking time bomb waiting to explode!
The conversation is never can you do a thing. It should always be, should you do a thing . . .
In North America the safety standards are well established and generally speaking are followed. Think NEC, CEC, UL, cUL, ETL, etc. The above are how things are supposed to be done and tested for safety while offering long term reliability.
When you purchase a 3rd tier product that offers absolutely no safety markings that should make you run. The infamous CE mark that appears on almost every Chinese electronics must always be suspect if displayed on a unknown brand / 3rd tier.
The Chinese are the undisputed leaders in copying anything which spans clothes to medicine for any price point. When people say the Chinese can’t build anything that last these people are simply ignorant and stupid.
The Chinese are motivated by profit like any other person. Almost every known piece of high technology is made in China. As an example regardless of what you feel about the brand. Apple doesn’t have China making their wares because their incompetent or will explode in two days.
Any company worth their salt has independent personal to QA / QC the production of the manufacturing line. They also have contracts which fully stipulates the BOM, QA, QC, meet a specific level at all times.
If they don’t they pay heavy fines and penalties. In the worst case they pull out. In the extreme case get sued.
As noted up above the Chinese are driven by profit. So these business don’t want to kill the golden goose! This scenario is played out by the likes of Apple, Google, Cisco, Intel, Samsung, name any company in the world.
It’s made to the highest quality and durability that the company is willing to pay for.
The same can not be said for every low priced 3rd tier product on AliExpress! Clearly it’s not because the Chinese can’t make it last, make it safe. It’s because there isn’t a 1st tier company sponsoring them to do so and their drive is market share and low profit.
If someone did a poll about how many members have replaced their NVR and how long it lasted. You’ll see a huge gap in longevity and the failure point(s). Keeping in mind hard drive failures are expected as they are consumables. Along with the fact your not going to see a purple drive inside a $89.00 NVR unless the customer paid for the same!
A all in one solution like a POE NVR has that undisputed allure of Plug & Play. It’s simple, cost effect, it just works!
Now, if you get 5 years out of it - Good 4 U!
If you get 10 you won the lottery and should enjoy that incredible feat.
Will people see the same now in 2021?
Ideally yes but probably no . . . If something blows up in a NVR the only thing the average person can do is replace the HD. Having all your eggs in one basket is asking for trouble.
Very few of us are made of money so know the reasons for being price conscious. But, this doesn’t mean installing every blue light special known to man?!?
Id love to post up some take over photos of installs I’ve seen over the years and the cheap ass gear used.
If your a business you really have no excuse not having a decent budget while using name brand hardware. As a consumer, that runs the gamut and my hopes are these same people come on this forum and others to get educated to do it right once.
If for what ever reason you must install the Chinese switch up there install a thermally controller fan next to the switch to promote air flow and keep the internal temps low.
If you get 10 you won the lottery and should enjoy that incredible feat. 
Id love to post up some take over photos of installs I’ve seen over the years and the cheap ass gear used.