MCP2210 (Microchip) has delays between chip select to data, data to data
The delays happen because the MCP22xx family of devices is allegedly based on general-purpose PIC16F145x MCU. This MCU has only a 8-bit hardware to convert a byte into serial code, Master Synchronous Serial Port (MSSP) module. The converter is only 8 bit, and there is no DMA or else. So every transfer must be firmware-initiated, byte by byte, that's why the delays. Plus USB overhead. As result, there are gaps about 30 us between bytes on the bus. This device looks like a kludge. There are numerous complaints about sluggish performance of these ICs on Internet.