MacBook Pro 15" i9 2019 - Usb ports, power and battery issues

Hello. I am writing to ask for your opinion on my MacBook pro 15" and its problems.

(A1990 Late 2019 Model with i9 Intel Processor)

Since I got it it has given me some serious problems with the battery (for example, reaching 20-30% it would occasionally shut off, then restart at 15%, then shut off again and on again at 5%, and so on until dead battery)

Initially I solved this problem with an SMC reset and then I didn't take it to assistance because being my work tool, I couldn't afford to waste time.

Over the next three years, some similar problem reoccurred and I always solved it with an SMC reset.

I also diagnosed the Mac with its diagnostic tool and no problems emerged. Battery in excellent condition and with few recharge cycles.

This week I had a much more serious problem:

• Friday after work I put the computer to sleep and took it home.
• Mac was shut down all weekend.
• On Monday I turned it back on and none of the usb-c ports worked: no connection to the monitor and no charging. The SSD, on the other hand, connected correctly and allowed me to backup it. I tried to do a couple of SMC resets with no result, so the battery slowly drained until it shut down.

I immediately took it to the Apple service center on Monday evening and after two days testing it, they told me that I would have to replace the logic board with a cost of almost 900 €.

I brought it home and today, after two days in charge without showing signs of life on any port, I plugged it in and everything works correctly (charging, display, usb drive, etc.)

So what's the problem with this computer?

Any suggestions?

I'm going crazy to think I spent 4k € on a work machine that is less reliable than a 200€ windows pc.