In short, most people won't be affected, unless you own a mansion or a home in an overpriced market such as SF or NYC.
Keep in mind that the standard deduction also doubled, so depending on your own situation, you may not even need to itemize your deductions, such as your mortgage interest.
Doubling the standard deduction may have a perverse inventive against borrowing less (or simply buying cheaper homes) as, depending on your situation, it may be better than itemizing.
I think it's debatable whether the mortgage interest deduction really plays heavily into a noticeable amount of people's decision to buy or not; unless you are having a hard time deciding to buy or rent, there are a lot of other, larger factors.
Finally, I believe that doubling the standard deduction and eliminating a number of other deductions is a small, first step towards creating a simpler tax code- such a code wouldn't be as useful for social engineering (help middle class buy more small homes) but there are plenty of benefits, too.
Enrolled Agents (EA) are very good on average as tax accountants. Not perfect, but if talk to them mid-reporting period and they'll have heard of new rules.
Beyond that, what you need to know about "professionals":
1) The job of a CPA is to collect their fees.
2) The job of a lawyer is to collect their fees.
3) "Professionals" rank larger entities ahead of individuals in fees and advancement.
Also, get a personal referral for a CPA.
Wait, they got rid of mortgage interest?
Since the internet told me to see a CPA, I did. And I was not happy at how limited his knowledge base was. I corrected him a few times during our meeting. We had a conversation about Mortgage Interest and this never came up.
Isnt the point of the certification to be the expert? I'm just a math guy that can read.