Unlike datacenters networks, ISP access network offering is mostly asymmetrical.
No matter what technology the ISP uses, you most probably receive X capacity for downstream/download and a fraction of X for upstream/upload.
Given the difference is mostly a pure commercial construction, there’s no standard downlink to uplink ratio we could assume.
Current multipath code accommodates a “capacity” attribute for each physical link but it’s a flat single number. For better usage of links in a Multipath scenario, I believe a capacity for uplink and another one for downlink should be accommodated.