Why is Publisher being phased out, and what is Microsoft replacing it with? Will Microsoft 365 be cheaper since they are phasing out the program?

Microsoft, continue to run supporters off. In the 90's they had the best photo program available, and I saved thousands of photos in their format and then it was gone, and no replacement program was available. I have tried everything since and none was better than their photo program to this day, but Microsoft think they know best. Think about how many versions of Outlook/calendar they have left you hanging with. Some folks never learn. It just looks like they are trying to force you to the other side.

Whilst I understand the need to rationalise products and a conversion to Word or Powerpoint is possible, this conversion only works adequately for fairly simple Publisher documents, and has a long way to go before this method is an acceptable option.
There are so many things that are easy to do in Publisher but much more difficult in Powerpoint and so convoluted in Word that it is not a valid option.
Powerpoint is primarily geared for producing presentation slides and not desktop publishing projects.
Word is capable of good desktop publishing projects, but requires far more knowledge, planning and effort than Publisher.
I have found that the Affinity series of programs (Design, Photo and Publisher) provide a far cheaper and flexible option and is both available on PC and MAC/iPad.

Unable to find a viable alternative to Publisher, I found the only solution is to download an old version of publisher. When I retired and then downsized and moved, I unfortunately discarded many old disc of programs including my old publisher programs for which I held a license. So I searched for and alternative and found that on PC World.com I could buy a download with a lifetime license of Microsoft Office Professional 2021 for $47.99 that will keep Publisher on my computer even after Microsoft pulls it from Microsoft Office 365 subscription service. It is working now on my Windows 11 desktop. And should continue to work when Microsoft abandons all of us who relied on them to serve their customers who have used Publisher for decades. I don't care that it won't be updated. As long as the features it has now continue to work. Microsoft could have continued to offer publisher at perhaps an additional cost and manybof us would have reluctantly agreed. But they chose to abandon customer loyalty. So go to PCworld.com and purchase a licensed download and keep working with publisher as you know it. Good luck.

I have been using Publisher since it's FIRST edition in the early 90s. I used it for laying out a newspaper. I still use it. I use Word for text documents with minimal graphics. I use PowerPoint for slide presentations. THERE IS NO COMPARISON between Word, PowerPoint and the ease and capabilities of Publisher. Anyone who thinks they are remotely similar is sadly delusional. I'll be switching to Open Office, Google, and Canva for any new material.

30 years of files down the drain, soon rendered useless by big Microsoft's failure to support it's long-term supporters.

The last thing I want to do at my age is find time to transfer all my 'writings' to PDF format from Publisher. I do not understand why Microsoft could not retain the Publisher program even if there was a cost to use it. I would be happy to pay for it. Publisher has been the perfect program for newsletters, brochures, and other documents that use photos, graphics, links, etc.

As mentioned earlier, I edit and write for a couple small non-profit organizations. Many of the products are printed and mailed rather than simply sent via e-mail to people who request information. A reality in this crazy world is the fact that many people over age 65 are not glued to their cell phones. Many prefer reading printed documents on paper that we can hold in our hands and refer to. It's easier on our eyes and on our brains. This decision to eliminate a publishing program that is so widely used by smaller groups/organizations is a shame. It sends a very negative message that says "You/We are not important."

Aside: Many who use Publisher are accomplished writers. AI may be helpful to a population that wasn't well educated in writing skills, but it is rather interfering to those of us who write well. This all makes me wonder what is going to happen to talents people have such as art and music. Why be creative if AI can create it all? Yes, I can see the good in AI, but making everything simple will destroy creativity.