Your critics are more applicable to the similar robotics kits of NVIDIA and Qualcomm, which range from a little overpriced to extremely overpriced, in comparison with their alternatives like single-board computers with ARM chips from Rockchip or the like, small computers with Jasper Lake or even with cheaper Tiger Lake models, NUC-like computers with Intel or AMD CPUs, or bargain laptops (all these are under $500, while the ARM or Jasper Lake/Elkhart Lake systems are under $300, with many slower ARM SBCs under $100; the NVIDIA and Qualcomm kits range from $400 to $2000).
These kits from AMD Xilinx, i.e. Kria KV260 and Kria KR260, are very cheap in comparison with the other development systems that include an FPGA so powerful.
Their main defect is that Xilinx makes extremely few of them, so if you want to buy one you might have to wait many months or even years.
For projects that would not benefit much from a FPGA, a cheaper SBC or even just a microcontroller board of $10 or $20 would be a better choice.
However, if you have a clever idea that could be implemented with an FPGA, these new development kits are better than most FPGA boards that have been available previously.
Their main alternative are various boards with Xilinx Artix-7 FPGAs. There are boards in the same price range of a few hundred $, with FPGAs of similar size to those of the Kria kits. However the older Artix-7 FPGAs are significantly slower than the UltraScale+ used in the Kria kits, and they also do not have the 64-bit ARM cores included in UltraScale+ (which has a quadruple Cortex-A53 running Linux and also two 32-bit Cortex-R5F ARM cores, for hard real-time applications).
These kits from AMD Xilinx, i.e. Kria KV260 and Kria KR260, are very cheap in comparison with the other development systems that include an FPGA so powerful.
Their main defect is that Xilinx makes extremely few of them, so if you want to buy one you might have to wait many months or even years.
For projects that would not benefit much from a FPGA, a cheaper SBC or even just a microcontroller board of $10 or $20 would be a better choice.
However, if you have a clever idea that could be implemented with an FPGA, these new development kits are better than most FPGA boards that have been available previously.
Their main alternative are various boards with Xilinx Artix-7 FPGAs. There are boards in the same price range of a few hundred $, with FPGAs of similar size to those of the Kria kits. However the older Artix-7 FPGAs are significantly slower than the UltraScale+ used in the Kria kits, and they also do not have the 64-bit ARM cores included in UltraScale+ (which has a quadruple Cortex-A53 running Linux and also two 32-bit Cortex-R5F ARM cores, for hard real-time applications).