How will investing be different in the future and 7 AAII Q&As

On July 22 Chris Pedersen spoke to the Orange County AAII Chapter.  This podcast, as well as one on 8/9/23 (20 Q&As) and another on 8/2/23 (16 Q&As) address questions that arose from the presentation.  This podcast covers a few more AAII questions plus other recent questions.
Topic 1:  What is the difference between investing today vs. 40 years ago?  And how  is  investing likely to be different in the future?
Topic 2:  Will the new Avantis All Equities Market Value ETF be a good substitute for your Worldwide All Value Portfolio?
Topic 3:  Do you recommend converting traditional IRA funds to a Roth IRA using the back door Roth IRA strategy?  Paul suggests reading:  https://www.thebalancemoney.com/when-does-a-backdoor-roth-ira-make-sense-4153803  and various articles at The White Coat Investors:  https://www.whitecoatinvestor.com/backdoor-roth-ira-tutorial/
Topic 5:  Should a younger investor (20s, 30s, 40s) put TIPs as part of their fixed income or just stick to the Total Bond Market?
Topic 6:  Can you discuss your recommendations for the bond portion of a portfolio?  For example, how do you decide how much would go with the Worldwide 4 Fund Portfolio?
Topic 7:  Could there be a problem when small cap value funds get too large?