A couple of points you make are highlighted
old fashioned terrace - it really is only a few steps I would never describe that as an old fashioned terrace
always 95% full - if by always you mean the past season or so?
Some facts here show that even the rugby was better attended than the football as recently as 2009
Average attendances
Bristol Rovers
Season Att League
2016–17 9,302 League One
2015–16 8,096 League Two Bristol Rugby
2014–15 6,793 Conference Att League
2013–14 6,420 League Two 5,808 Championship
2012–13 6,308 League Two 4,859 Championship
2011–12 6,035 League Two 5,351 Championship
2010–11 6,253 League One 4,273 Championship
2009–10 7,042 League One 5,261 Championship
2008–09 7,170 League One 7,435 Premiership
2007–08 6,849 League One 9,175 Premiership
2006–07 7,931 League Two 10,152 Premiership
https://en.wikipedia.org/wiki/Memorial_Stadium_(Bristol)