I think a lot of the anti-Microchip people are basing opinions on the older architectures and heresay.
Everyone has different requirements. From my point of view, these are some of the reasons I like Microchip. I can't compare with others as I've yet to feel the need to look elsewhere.
Availability - this has always been a strong point. While all the ST/NXP/whoever people are tearing their hair out right now trying to get parts, I can still get pretty much any PIC I need from Digikey. And if a particular part is thin on the ground, there's a very good chance there is either something pin-compatible that is available, or the same part in a different package
Devtools - maybe a bit controversial, and admittedly I don't do big projects, but the fact that I can use exactly the same IDE AND programmer , with the same ISP header, for everything from a 6-pin PIC10F to a 200MHz PIC32MZ part saves me a ton of learning time.
The fact that the whole IDE and toolchain is well integrated means that where needed, I can give a customer my project directory, tell them to install MPLABX, buy a Pickit 3, and they can be up and running in 10 minutes.
One instance I recall this being invaluable was when a customer with zero MCU knowledge wanted to be able to create different LED brightness curve lookup tables.
Similarity of peripherals across the range - again, from an 8 bit to a 32 bit part, a lot of the peripherals (and peripheral register names) are either exactly the same, or similar enough that there is minimal learning curve. On the larger parts with more complex peripherals, they tend to default to working the same way as the lower-end ones until you explicitly configure them otherwise.
Even stuff like self-programming for bootloaders is very similar across the whole range.
Pin mapping flexibility - this varies across the range, but in most cases there is enough flexibility in mapping pins and/or choice of multiple peripherals (UART1 vs. UART2 etc) that PCB layout is greatly simplified.
Package flexibility. Most parts from 8 bit to 32 but have a choice of 3 or 4 packages - DIP,SO,SSOP, DFN/QFB, QFP. Yes, 32 bit parts in DIP or a 20 pin SSOP or QFN20. In many cases a wide range of pin counts for the same basic part.
Pre-programming - MicrochipDirect will preprogram , mark and re-reel PIC10s for about 4 cents, with about 1 week leadtime and negligible setup cost. PIC32s from memory about 30c. AFAIK no other manufacturer offers this, and third-party programming services can cost more then the chips. Digikey has a programming service but only for US customers. Pickit 3's programmer-to-go functionality is also extremely useful for production by subcontractors - just send them a pre-loaded programmer, and all they need to do is connect and press a button.
Alternatively I can easily talk them through setting up a pickit 3 themselves.
MIPs vs. ARM is simply not an issue when everything is in C.
Yes the 8-bit architecture sucks, but C hides most of it well enough to rarely be a problem. I've done projects with application and a serial bootloader in the 512 words of a PIC10F, all in C.