Very much this. Listening to Apple execs talk about this topic, they stressed they go through thousands of customer responses and try to figure out what people want in terms of ports. The number of ports available on the sides is by necessity limited. There's only so much space that isn't crowded out by things like speakers or batteries. They can't provide everything, so they provide ports THAT CAN BE EVERYTHING. Yes, we might need a different cable or dongle, but none of the ports are limited. People compare this to the 2015 MacBook Pro which had different ports. But USB-C was not widely available then and was just starting out. Virtually no one used it then. Mac products then used Thunderbolt 2, which resembles the mini-DisplayPort connector, which was not truly multi-purpose. The Thunderbolt 3/USB-C ports are true multipurpose ports that literally can do anything we want it to do within reason, and that includes power delivery, SD cards, Ethernet, every type of monitor connection, USB 2.0, 3.0, or 3.1.
Those who demand SD card slots can still have an SD card capability, but if Apple provided that, there's one less port that can connect to our second or third monitor (Just because one person doesn't want three monitors doesn't mean someone else doesn't). If Apple provided an Ethernet port (what I wanted most but knew would never happen), you can't add an SD card or ordinary USB peripheral with that port. I find it funny people are complaining because Apple provided the absolutely most flexible assortment of ports on the planet. We can literally connect every modern laptop peripheral we want with any of the four ports.
Phil Schiller mentions he carries dongles around. He knows it's a tradeoff and he's the guy who sets Apple's hardware requirements because he's responsible for market research. He's willing to inconvenience himself in order to give all customers maximum flexibility. He could have had the hardware department cater to his own needs so he doesn't have to carry dongles, but he knows his requirements aren't everyone's. Yes, it is an inconvenience to use a dongle or to find the right cable. But the greater good is served because no one is limited on anything they want to do. Want to hook up three monitors? Go for it. Want a SD card adapter, one monitor, and an external hard drive? Go for it. Want to hook up an eGPU, an iPad, and a MIDI keyboard? Go for it. There are an infinite number of combinations you can have with those four ports. And people complain... SMH.
Or i have a person who all they needed to do was a firmware update on the hardware to fix the problem. So it could not be the Mac hardware is the problem but the software is old or never has been upgraded. Hmmm why does Windows release an update every other month 
