My wife arrives at CDG tomorrow morning on UA and needs to catch a TGV in Terminal 2. We did this trip regularly before 2020, but this is the first time that either one of us has been to T1 since it reopened. Is the arrival at T1 and transit to T2 generally the same as it was before? If not, what are the differences that we should know about?

Yes, essentially what it was before (CDGval to T2).

No difference and very easy : go landside in T1, take CDGVAL for the whole line. The last station is adjacent to TGV station.

Yep - she said it was exactly as she remembered it. Funny - I had actually gotten a little nostalgic about T1, even with all of its quirks, so I am happy to be back there on UA instead of T2.

[UPDATE on T1] Just traveled out of T1 at CDG and wanted to report on some of the changes. In general, it is a much nicer experience now. Immigration is pretty much the same as it was before, but almost everything after that is different. The stores and lounges have moved to a new building next to T1 they are both now after security. The Star Alliance lounge is a huge improvement - much bigger and much nicer (with actual windows so not so gloomy inside). Since the lounge is now after security and because the gates and the lounges are in the same building, it is much easier and quicker to get from the lounge to the gates. All in all, I found it a much better departure experience.

After recently departing and arriving here, I'd have to say it's very impressive and I like the experience better than T2. The last time I had departed here, the *A lounge was closed but I found passing the time in concourse very pleasant. The furniture has nice chic theme, comfortable, very clean and essentially brand new--my seat was so comfortable, I dozed off. I didn't have time to peruse the shops and restaurants, but will definitely do so next time.

T1 is fantastic, in my view. I'd be hard pressed to think of another airport I'd rather pass the time waiting for a flight, unless it's in a super premium lounge or something.

PS - T1 sure beats that AF lounge they have in the K concourse, which is nothing like the one in the L gates.