Can't install dota on ubuntu

[kheuton]

I've tried both the latest (ubuntu-20) as well as the ubuntu-18 image, and attempting to install dota fails with a cryptic error.

I use the following command: sudo docker run -it steamcmd/steamcmd:latest +login [my user] [mypw] +app_update 570 +quit

The game downloads and verifies the download, before showing the following:

 Update state (0x101) committing, progress: 8.62 (3868444206 / 44888062441)
 Update state (0x101) committing, progress: 15.71 (7053480492 / 44888062441)
src/clientdll/compatmanager.cpp (1988) : BFileExists( strSteam2WrapperSrcPath.String() )
assert_20221016233508_217.dmp[238]: Uploading dump (out-of-process)
/tmp/dumps/assert_20221016233508_217.dmp

assert_20221016233508_217.dmp[238]: Finished uploading minidump (out-of-process): success = no

assert_20221016233508_217.dmp[238]: error: libcurl.so: cannot open shared object file: No such file or directory

assert_20221016233508_217.dmp[238]: file ''/tmp/dumps/assert_20221016233508_217.dmp'', upload no: ''libcurl.so: cannot open shared object file: No such file or directory''

Error! App '570' state is 0x10C after update job.
Updating Workshop items for App '570'.
 Update state (0x3) reconfiguring, progress: 0.00 (0 / 0)
 Update state (0x1) running, progress: 0.00 (0 / 0)
 Update state (0x61) downloading, progress: 29.80 (19715096 / 66151330)
Work thread 'CContentUpdateContext::m_pCPUTh' is marked exited, but we could not immediately join prior to deleting -- proceeding without join

The key line seems to be src/clientdll/compatmanager.cpp (1988) : BFileExists( strSteam2WrapperSrcPath.String() ), and the things about libcurl.so are a red herring about uploading the minidump without a 32-bit curl library.

Installing other games (cs:go) works fine. Any idea where to start looking?