[johncolanduoni]

Yes, HTTP/2 requests run on separate streams and will interleave chunks. They still have some head of line blocking however, since the TCP stream will not allow reading from another stream while waiting for another stream’s chunk to retransmit (for that you need HTTP/3).

[tehbeard]

HTTP/1 requests (uploads in this case) are also separate to some degree (though there are fairly stringent limits on connections per domain iirc which HTTP/2 resolves via the mentioned streams/multiplexing of connections).

The problem they have specifically would be that in a single request (form post for example) those uploads will be linear.

Solution really boils down to paralellizing the upload, using protocols/standards like https://tus.io/ or S3-compatible APIs to push the data up then syncronize with a record/document on the server.