The dead logic board of MacBook pro 2020

On 27th October my mac pro simply shut down without any reaction to the power button and other suggestions that apple has mentioned on its site.

I live in Paris so I searched for an icare center and gave them my mac for repair. I asked for a backup of the data. They told me it takes 5 to 7 days to check up on the mac carefully and then 2 days for repair.

By the evening of the very day, they sent me an email that claimed they changed or reinstalled a new chip in the power system, and my mac run perfectly. 

The next day I picked my mac up with zero cost money, and after 3 days the same story happened!

Again on the first Nov., I gave my mac to the same repair center. after one day they sent me a bill of 765€ with a diagnosis of a dead logic board plus 180€ for saving my data which is refundable if they didn't succeed to do so!

First: my MacBook is 2020, and as I know, 2 years of a common user can not damage the motherboard.

Two: if there was such a problem why apple service center didn't notice at first and just changed a chip for free?

Three: if there was not a problem the wrong course of action may have caused this damage. 

I sent the director of the center an email to ask for the reason and in return, he told me: “ the chip that manages the power supply, is located on the motherboard. If the power supply chip had gone to safety, then the motherboard had a problem. We reset it and it worked (often this fixes the problem permanently), we were not going to give you a motherboard issue at that time since the computer was working again, at the risk of the failure occurring again. ”

And further he told me they were kind enough by not charging me for the first time!

What I needed was an expert to diagnose my laptop’s problem and fix it not kindness. 

Is this normal that Apple repair service is working based on trial and error method for repairing laptops and if the repair didn’t go well, ok now we can replace it with a price that is very close to the real worth of your laptop!

That is my responsibility to have a backup. So true and no arguments, but in the first repair I asked for a backup and when I addressed this in my email he told me that because the mac was running well that was not necessary to make a backup. 

Just can say if it is a problem with the mac that's so embarrassing such a product stop functioning just after 2 years.

And if there is a fault of bad diagnosis and wrong repair, again is so disgraceful for such a brand as Apple.

2 questions:

1. Is it reasonable to fix it with this price?

2. Is it possible to ask just save the data and not logic board replacement? Is it even possible?

Thank you all.