Personally I would treat CAT5e as a minimum, there is hardly any cost difference between gigabit and 10/100 switches and 802.11ax routers are normally gigabit anyway. I'm wiring our bungalow with CAT6 as the cost premium compared to CAT5e copper was negligible, and with a rural broadband subsidy our fibre connection delivers 300mb at the lowest price tier – if I could afford it 900mb is available over the same hardware.
I'm not sure that the installation requirements for CAT6/6a are that onerous, after all, minimum bend radii apply to all cables, and unlike power cables, if you go below the minimum, the worst that would be likely is a drop in speed, not a fire. (Probably not anyway, 10GBASE-T or POE might get warm).
If you do choose to go CAT5e or below, you might want to consider CCA (Copper-Coated Aluminium) cable which is less than half the price of copper. It is cheap enough to make it worthwhile doubling up on cable connections rather than using additional switches to get an extra connection in a remote location.
Brian G
Edited By Brian G on 04/09/2021 12:36:53
Edited again as I forgot to insert the link to Kenable for CCA cable.
Edited By Brian G on 04/09/2021 12:38:41