I'm sure the BBC have already announced they will be showing a lot of highlights over the festival weekend?
Actually I just found the link: https://www.nme.com/news/music/coronavirus-bbc-confirms-details-of-glastonbury-and-eurovision-replacements-2634111
On the last weekend of June, the broadcaster will also air the “Glastonbury Experience”, which will allow fans to enjoy classic performances from the comfort of their own homes.
“Glastonbury may have had to cancel its 50th anniversary festival this June, but we are still working to mark the weekend with a Glastonbury experience to celebrate the spirit of this unique event,” the BBC said.
“We will bring the nation together and create a weekend of the best in music across radio, television and online with amazing performances for you to enjoy in the comfort of your home. And we will be in touch shortly with more details of the weekend.”
EDIT: Sorry, I misread your post. The above is in relation to highlights of previous festivals. Not a bad idea to have some streams from this years acts but guess that's very much down to the artists themselves.