Slightly out of date but make sure you read this:
Time to open up Test cricket?
Saves me making what I see as an unanswerable case.
I have not read that article before, but i have heard the arguments before & i don't agree with with it.
As i mentioned before "test cricket" is unusual sport & its very difficult to master. Look at cricket history most teams took a VERY LONG TIME to conquer it after ENG & AUS:
S Africa debut in 1888 - they technically were truly competitive as a side until the their 1950s team. That's 60+ years (40+ excluding the war years)
Windies debut in 1928 - didn't become competitbe until the famous 1950 series win in ENG. 22 years (15 excluding the WW2)
NZ debut in 1932. Won first test in 1956, didn't seriously become competitive until their 1961/62 series vs S Africa. 30 years (23 excluding WW2)
IND debut 1932. Won 1st test until 1959. Were not seriously competitive until the mid 60s when their great spin quarter started emerging to make them a force at home.
PAK debut in 1954 & won their first test & series within the first 3 years of their status. Generally you can they adapted to test cricket faster than any team in history, since they never had a real minnow phase.
SRI debut in 1982 & pretty much became solid & test/general cricket after the 1996 world cup. 14 years.
ZIM debut in 92, won 1st test in 94, first series in 97 & were looking very good at one point in the lae 90s/early 2000s as a test nations before political strife has pushed them back 20 years a test nations. Realistically they should not have been given back test status.
BANG - have not made any significant progress in a decade & its debatable whether the test team will soon, although the ODI/T20 teams is showing some fight.
This historical trend shows clearly proving to be a good test team takes a long time, so that sanctity of it needs to be protected.
As i said, the easiest approach is for ICC to utilize cricket luxury of the 3 formats & let the associates prove themselves first in 20 & 50 overs cricket, their country has to fall in love with the sport currently in a society that lives for fast sports that finish in 3 hours, get the right infrastructure & first class system with ICC help - then they can move up the formats.
Makes no sense to allow another team to play test cricket if they have not done this & take 10 years to become good. Test them & their countries appreciation for cricket first in the limited overs formats.