This is true but also very complicated. I have tried very expensive microphones and I have tried cheap microphones and which one is better is conditional to location, and deployment.
I use a røde lavalier tieclip which is awesome, and surprisingly cheap. It's also very omni. I had a USB-C enabled podcaster microphone which was awesome and very directional but it also was a giant lump in front of my face in zoom.
On the whole, a tieclip and some minor level setting works, but I just can't control the lawnmower outside and with an Omni, it's leaking in.
getting high Q sound and directionally limited but not in your face in anything but a pro sound studio is hard. I suspect the sound isolation in a studio also has some issues: a certain amount of the real world leaking into your voice isn't a bad thing. "it depends"
also: get trained. My company paid for me to do a course with the Australian Film and Television School and it was delivered by a far north queensland radio professional who was not condescending, not nasty, and very good at explaining how to do speak-to-microphone without a crew to help you. Worth every penny. Oh yea: those "ad hoc" recordings? 99% planning. There is no such thing as ad hoc in the radio, if you can avoid it.
