Is there an upper limit to the number of lines a report can have in View?
There is no limit as to how many lines there can be in a SYSOUT collected by View.
The only true limit would be the amount of available data space on the database.
View can use the SARINIT MAXLINES parameter, to control how much of a report gets archived to disk, or TAPECLSL can be used to archive a report directly to tape, to avoid having the report on the database's disk layer.