I agree. Developers often assume that everyone has the latest flagship laptop. A large majority, particularly in developing countries, only have access to $200-$400 laptops that struggle at running modern applications.
We either have to focus on making our applications more efficient, as we did 10 or so years ago, or make high performance computers more accessible.
I think for many that is a hard drive thing combined with dozens of tool bars, though. Phones have solid state memory so that shouldn't be a major problem.
The solid state memory in phones is a far cry from anything in your computer though and we regularly see devices with storage that's noticably slower than even mechanical HDDs.
Think about flash storage on phones to be more in class of a fast SD card, not the SATA3 SSD in your laptop.