I do not know what you have read about these boards but I see no sign of any heat sinks on any of the other entry level development boards from the major manufacturers. For my purpose which is learning about these devices the board appears quite suitable, especially considering the cost compared to the alternatives.
You probably missed the point, then. The board you showed sports Artix-7/100T or 200T, which are already BIG FPGAs. Most "entry-level" boards out there with Artix-7 parts only sport an Artix-7/35T or so.
One example of board from Digilent with a 100T is this one:
https://store.digilentinc.com/usb104-a7-artix-7-fpga-development-board-with-syzygy-compatible-expansion/I wouldn't call it "entry level". That said, it doesn't seem to come with a heatsink. But I would seriously consider adding one if I were going to do anything "serious" with this board.
Point is, 100T (and all the more 200T) can dissipate A LOT of power, and a simple review of the schematics (that QMTECH kindly provides) shows that power supplies are undersized if you want to use the FPGA at its full potential. It can also be seen that decoupling is a bit on the low side.
As to heat dissipation, even a 35T will get pretty hot while running depending on your design, but a heatsink is usually not required. A 100T or 200T? Things will get hairy. That said, you can always add a heatsink on the FPGA yourself. The onboard power supplies are more problematic.
Anyway, unless you really need some FPGA this big (I don't know what you want to do), I'd highly suggest going for a more modest Artix7-35T. Those will dissipate a lot less power, and for those, QMTECH boards are usually adequate. But maybe, just maybe, you're interested in this board not for the "large" FPGA itself, but for all the connectors?