How is IB different from RB nowadays?

OK, rather than ridiculing, I'll help the OP.

There appears to be a misunderstanding of the term IB, Although the "I" stands for investment, this is not the same as the retail bank folks who do investment management. Those are referred to as Wealth Managers, Investment Advisors, Investment reps, etc and do indeed work with many of the same branch clients as the rest of the retail bank. The focus here is on RETAIL. These are the people who help individual investors accumulate wealth.

IB (Investment Banking) is "institutional" and provides access to capital (debt and equity) to the largest companies in the world. That capital allows companies to invest in their business by building new factories, buying other companies, developing new products, etc.

Although both deal with investing, these are two very different buckets within the Financial Services Business.

The people on WSO primarily care about IB.

Now, regarding what you were ,I think , meaning to ask, the retail investment advisor sitting in a BofA branch works pretty closely with the rest of the branch staff including the personal banker. Together they try to get as much "wallet share" from a client as possible. "We can do your checking, savings, home mortgage, personal loan, IRA, and other investment accounts". The more lines they have, the "stickier" the client becomes and therefore the more profitable the client is.

Hope that helps.