I agree with everyone that it is a bit annoying but I’ve found it’s not nearly as bad as it seems in reality - obviously this is just my experience and take it for whatever it is or isn’t worth.
I’ve been going through a mortgage application process which needs reams and reams of paperwork including bank statements and have found Monzo customer support will produce them instantly and supply a PDF file - they look good and have all the expected information on them and the mortgage company etc were perfectly happy with it in the end. Just to hedge my bets in case of problems with the PDF version, I also requested a stamped paper version which arrived just a couple of days later in the post.
In contrast, my legacy bank do allow you to export statements directly from the online banking, but it turns out they only do them in 3 month blocks and only at the end of that block (so, for example, you can’t get a statement covering November and December until the 3 month block they’re included within has concluded) and there was no obvious method for requesting paper should you wish to. Having gone through the process with both banks, actually Monzo turned out to be much less trouble then the other bank, and a pleasant surprise on that front.
Bearing in mind that this is their “internal quality”, not-a-proper-feature version of the functionality which is still beating at least one big bank, it can only improve.