I read in another thread recently that the OP had used ThomThom’s Component Replacer plugin to good effect, to turn exploded individual geometry into components and vastly reduced the file size…
And also, i had one model that reached 90mb because i hadn’t used groups or components at all… I scrpped it and started again, much cleaner, and the new replacement of the old model looks the same, but is only 7mb… It can be better to start over sometimes, and i promise it takes far less time second time around