You can have a number of problems at any particular time for whatever reason the IO decides to make one for you. A long history of stamps, entries, tourist visas may not ever be a problem, or it could be a big problem, you never know. It does seem to be more of an issue when applying for a tourist visa though, which is what the post is about. In this case to prevent any further problems at a consulate, a new passport is required. If entering on a VE then he might be alright for a while (until he isn't)
This post is literally regarding his problems in getting a SETV which got denied due to previous visas and entries and you are recommending him to go and try to get another one which might get refused. Go and get a new passport and clear all the old stamps and tourist visas, then you won't have any issues at a consulate for a few more years.
That is pretty irresponsible advice. You can be pulled up at any time at a consulate or on arrival to Thailand and be questioned, even though they are on separate systems. Too many stamps, exemptions, tourist visas can be a problem in both circumstances.
When it is a legitimate visa for a legitimate reason, they generally don't harass you at consulates. It is only overuse of tourist visas by people who are not really tourists.