Been asking for it for a long long time!
The problem is Bangladesh being so ****. They got it mainly because of the pressure from India/Pakistan/SL who saw letting them in as a chance to cement their power base. They get Test status and then prove to be little more than whippings boys. That in itself diminishes the desire to add more teams to the Test roster. I fully understand not wanting to demean Test match cricket. It is the pinnacle of the game, and should be protected. The problem is you are in a catch 22 situation. How are Ireland, or any other wannabe Test standard team supposed to reach Test match standard if they aren't even allowed to play 5 day games? They have to make do with games against other non Test teams and the very rare one day or T20 game against a test side. In effect, Ireland are expected to reach Test match level by playing teams who aren't good enough for Test match level in a different format to Test matches. That's just never going to happen.
Here Andy Murray, warm up for Wimbledon by playing games against your granny on my driveway. Now go compete on an even level with Nadal/Djokevic.
The ICC talk, laudably, about wanting to expand the interest in cricket, but how can you do that whilst denying teams access to the pinnacle of the game? "Come play our sport, it's really good. PS, you'll be worthy of playing the top level!"
This is why I think the 2 tier test system is best. The top tier stay as it is, then you introduce a second tier, Ireland, Afghanistan, Zimbabwe (politics aside), maybe Bangladesh and a couple of others (Holland, Scotland etc). That way they get to play tests and they get a little experience against the bigger boys. Be it through a promotion relegation system (most probably a play-off to allow the bottom ranked top tier side maximum opportunity to stay up, or if you want that another way, to minimise any chance of a lesser nation earning the right to play the big boys), or by the odd one off test here and there. I fully expect the one off tests, or wonder of wonders a two test "series" to be against the reserves or B-teams of the big test sides. I also expect the snobs/wankers, Beefy I'm looking at you, to deride anything any of these Tier two teams do as "Only tier 2 cricket" BUT it is a start and the only realistic way anyone has of getting near Test level.
The alternative is to wait for Ireland/Afghanistan etc to magically develop 11 test match players out of thin air!