The modern equivalent to that experience is through cheap microcontroller development boards. I recommend the RISC-V based ones (e.g. ESP32-C6, CH32V, GD32V, K

The modern equivalent to that experience is through cheap microcontroller development boards. I recommend the RISC-V based ones (e.g. ESP32-C6, CH32V, GD32V, K210). Some SBCs double as development boards, with huge GPIOs capable of a lot besides basic I/O (PWM, I2C, SPI, UART, I2S...) The new, RISC-V based, "VisionFive 2" is a lot of fun.