[davidmanze]

It is being talked about R5 and  overheating issues
However 30 minutes shooting is understandable ( and expected by many) IMHO  however thuis limit is only valid at 23 degrees in the shade, if you are shooting in sunlight in hotter temperatures it should be  even lower.
Let's also keep in mind that 8k 30 minutes that's 200GB
to have an idea about how many people do need this let's see how many are using 250GB cards and up with adequate speeds of at least 150Mb/s

Canon's official overheating specs:

20 mins of 8K recording at 23°C in the shade before overheating ......... recovery period 10 mins (cool down) for another 3 mins recording ....... 20 mins cool down for 8 mins further recording.
.... 4K@60 Fps .... 35 mins recording ..... cool down 10 mins for a further 10 mins.
.... 4K @30 Fps ... 30 mins recording ..... similar cool down .....

... and how long will it record for example here, where it is 33°C in the shade?? ...... and worse in full sunshine ?? .... many are predicting 1/3-1/2 of the time quoted.

 ..... sensor overheating that has been a main headline of 4K video ....... and Canon did well to not mention a word about it ..... it had to be dug out by Utube reviewers!

P.S. ..... there is also a 30 minutes video time limit ....